ou are unloading a refrigerator from a delivery van. The ramp on the van is 5.0 m long, and its top end is 1.4 m above the ground. As the refrigerator moves down the ramp, you are on the down side of the ramp trying to slow the motion by pushing horizontally against the refrigerator with a force of 370 N . Part A How much work do you do on the refrigerator during its trip down the ramp

Answers

Answer 1

Answer:

Explanation:

component of force along the ramp

= 370 cos θ where θ is the slope of the ramp with respect to ground.

sinθ = 1.4 / 5

θ = 16 degree

370 cos16

= 355.67 N

Work done

= component of force along the ramp x length of the ramp

= 355.67 x 5

= 1778.35 J


Related Questions

A 7.35 H inductor with negligible resistance is placed in series with a 14.1 V battery, a 3.00 ? resistor, and a switch. The switch is closed at time t = 0 seconds.

(a) Calculate the initial current at t = 0 seconds.

(b) Calculate the current as time approaches infinity.

(c) Calculate the current at a time of 6.25 s.

(d) Determine how long it takes for the current to reach half of its maximum.

Answers

Answer:

(a). The initial current at t=0 is zero.

(b). The current as time approaches infinity is 4.7 A

(c). The current at a time of 6.25 s is 4.33 A.

(d). The time is 1.69 sec.

Explanation:

Given that,

Inductance = 7.35 H

Voltage = 14.1 V

Resistance= 3.00 ohm

(a). We need to calculate the initial current at t = 0

Using formula of current

[tex]I=(\dfrac{E}{R})(1-e^{\dfrac{-tR}{L}})[/tex]

Put the value into the formula

[tex]I=(\dfrac{E}{R})(1-e^{\dfrac{-0\timesR}{L}})[/tex]

[tex]I=(\dfrac{E}{R})(1-1)[/tex]

[tex]I=0[/tex]

(b). We need to calculate the current as time approaches infinity.

Using formula of current

[tex]I=(\dfrac{E}{R})(1-e^{\dfrac{-tR}{L}})[/tex]

Put the value into the formula

[tex]I=(\dfrac{14.1}{3.00})(1-e^{\dfrac{-\infty\times3.00}{7.35}})[/tex]

[tex]I=\dfrac{14.1}{3.00}(1-0)[/tex]

[tex]I=4.7\ A[/tex]

(c).  We need to calculate the current at a time of 6.25 s

Using formula of current

[tex]I=(\dfrac{E}{R})(1-e^{\dfrac{-tR}{L}})[/tex]

Put the value into the formula

[tex]I=(\dfrac{14.1}{3.00})(1-e^{\dfrac{-6.25\times3.00}{7.35}})[/tex]

[tex]I=4.33\ A[/tex]

(d). We need to calculate the time

Using  formula of current

[tex]I=(\dfrac{E}{R})(1-e^{\dfrac{-tR}{L}})[/tex]

Put the value into the formula

[tex]2.35=(\dfrac{14.1}{3.00})(1-e^{\dfrac{-t\times3.00}{7.35}})[/tex]

[tex]ln(0.5)=(\dfrac{-t\times3.00}{7.35}})[/tex]

[tex]t=\dfrac{(\ln(2)\times7.35)}{3.00}[/tex]

[tex]t=1.69\ s[/tex]

Hence, (a). The initial current at t=0 is zero.

(b). The current as time approaches infinity is 4.7 A

(c). The current at a time of 6.25 s is 4.33 A.

(d). The time is 1.69 sec.

Three equal point charges, each with charge 1.45 μC , are placed at the vertices of an equilateral triangle whose sides are of length 0.400 m . What is the electric potential energy U of the system? (Take as zero the potential energy of the three charges when they are infinitely far apart.)

Answers

Answer:

[tex]U=0.142J[/tex]

Explanation:

The electrostatic potential energy for a pair of charge is given by:

[tex]U=\frac{1}{4\pi E_{o}}\frac{q_{1}q_{2}}{r}[/tex]

Hence for a system of three charges the electrostatic potential energy can be found by adding up the potential energy for all possible pairs of charges.For three equal charges on the corner of an equilateral triangle,the electrostatic energy given by:

[tex]U=\frac{1}{4\pi E_{o}}\frac{q^2}{r}+\frac{1}{4\pi E_{o}}\frac{q^2}{r}+\frac{1}{4\pi E_{o}}\frac{q^2}{r}\\ U=3\frac{1}{4\pi E_{o}}\frac{q^2}{r}\\[/tex]

Substitute the values as q=1.45μC and r=0.400m

So

[tex]U=3\frac{1}{4\pi E_{o}}\frac{q^2}{r}\\ U=3*(9.0*10^9N.m^2/C^2)(\frac{(1.45*10^{-6}C)^2}{0.400m} )\\U=0.142J[/tex]

You have built a device that measures the temperature outside and displays it on a dial as a measure of how far away from room temperature outside is. The way the dial works is that a needle with a charged ball on the end is placed between two charged parallel plates. The strength of the uniform electric field between the plates is proportional to the outside temperature. Given that the charged ball on the needle has a charge of?

Answers

Answer:

m=33.734 grams

E=41435.95 N/C

Explanation:

The detailed explanation of Answer is given in the attached file.

A loading car is at rest on a track forming an angle of 25◦ with the vertical when a force is applied to the cable attached at C. The gross weight of the car and its load is 5500 lb, and it acts at point G. Knowing the tension in the cable connected at C is 5000 lb, determine (a) the acceleration of the car, (b) the distance the car moves in 20 s, (c) the time it takes for the car to return to its original position if the cable breaks after 20 s.

Answers

Answer:

Check attachment for solution

Explanation:

The motion of the car along the inclined plane reduces the force required

to pull the car upwards.

The correct values are

(a) The acceleration of the car upwards is approximately 0.09 ft./s².

(b) The distance the car moves in 20 s. is approximately 18 ft.

(c) The time it takes the car to return to its original position is approximately 1.[tex]\underline{\overline {1}}[/tex] seconds.

Reasons:

(a) Component of the car's weight acting along the incline plane, [tex]W_\parallel[/tex] = W·sin(θ)

∴ [tex]W_\parallel[/tex] = 5500 lbf × cos(25°) ≈ 4984.69 lbf.

The force pulling the car upwards, F = T - [tex]W_\parallel[/tex]

Which gives;

F = 5,000 lbf - 4984.69lbf = 15.31 lbf

[tex]Mass \ of \ the \ car = \dfrac{5500}{32.174} \approx 170.95[/tex]

The mass of the car, m ≈ 170.95 lbf

[tex]Acceleration = \dfrac{Force}{Mass}[/tex]

[tex]Acceleration \ of \ the \ car = \dfrac{15.31}{170.95} \approx 0.09[/tex]

The acceleration of the car, a ≈ 0.09 ft./s².

(b) The distance the car moves is given by the kinematic equation of

motion, s = u·t + 0.5·a·t², derived from Newton Laws of motion.

Where;

u = The initial velocity of the car = 0 (the car is initially at rest)

t = The time taken = 20 seconds

a = The acceleration ≈ 0.09 ft./s²

∴ s ≈ 0 × 20 + 0.5 × 0.09 × 20² = 18

The distance the car moves, s ≈ 18 ft.

(c)  If the cable breaks, we have;

Force acting downwards on the car = Weight of the car acting on the plane

∴ Force acting downwards on the car = [tex]W_\parallel[/tex] = 4984.69 lbf

Therefore;

[tex]Acceleration \ of \ the \ car downwards, \ a_d = \dfrac{W_\parallel}{m}[/tex]

Which gives;

[tex]a_d = \dfrac{4984.69 \ lbf}{170.95 \ lb} \approx 29.16 \ m/s^2[/tex]

The time it takes car to travel the 18 ft. back to its original position is given as follows;

s = u·t + 0.5·a·t²

The initial velocity, u= 0

Therefore;

[tex]t = \mathbf{\sqrt{\dfrac{2 \cdot s}{a} }}[/tex]

Which gives;

[tex]t = \sqrt{\dfrac{2 \times 18}{29.16} } \approx 1.\overline {1}[/tex]

The time it takes the car to return to its original position, t ≈ 1.[tex]\overline {1}[/tex] seconds

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a. A 65-cm-diameter cyclotron uses a 500 V oscillating potential difference between the dees. What is the maximum kinetic energy of a proton if the magnetic field strength is 0.75 T? b. How many revolutions does the proton make before leaving the cyclotron?

Answers

The maximum kinetic energy of a proton in a cyclotron with a 500 V potential difference is 8.01 x 10^-17 J. To determine the number of revolutions the proton makes before exiting, we would need additional information or formulas, which are not provided.

The maximum kinetic energy (KE) of a proton in a cyclotron can be calculated using the equation KE = qV, where q is the charge of the proton (1.602 x 10-19 C) and V is the potential difference. For a cyclotron with a 500 V potential difference, the maximum kinetic energy of a proton is KE = (1.602 x 10-19 C)(500 V), which equals 8.01 x 10-17 J.

The number of revolutions before leaving the cyclotron is dependent on the proton's path radius and speed. The magnetic field strength and the cyclotron's diameter allow us to determine these quantities. However, without the necessary formulas or additional information regarding the specific cyclotron dynamics, we cannot calculate the exact number of revolutions. In general, a proton in a cyclotron moves in a spiral path, gaining speed with each pass until it reaches the cyclotron's edge.

a. The maximum kinetic energy of a proton in the cyclotron is [tex]$\boxed{1.6 \times 10^{-12} \text{ J}}$.[/tex]

b. The number of revolutions the proton makes before leaving the cyclotron is [tex]$\boxed{27}$.[/tex]

a. To find the maximum kinetic energy of a proton in the cyclotron, we can use the relation between the kinetic energy (KE) of a charged particle in a cyclotron and the oscillating potential difference (V) applied between the dees. The maximum kinetic energy is given by:

[tex]\[ KE = qV \][/tex]

 where [tex]$q$[/tex]is the charge of the proton and [tex]$V$[/tex] is the potential difference. The charge of a proton is approximately[tex]$1.6 \times 10^{-19}$[/tex] Coulombs.

 Given that the potential difference[tex]$V$[/tex]is 500 V, we can calculate the kinetic energy as follows:

[tex]\[ KE = (1.6 \times 10^{-19} \text{ C}) \times (500 \text{ V}) \][/tex]

[tex]\[ KE = 8 \times 10^{-17} \text{ J} \][/tex]

 However, this result does not match the boxed answer provided. Let's re-evaluate the calculation with the correct order of magnitude:

[tex]\[ KE = (1.6 \times 10^{-19} \text{ C}) \times (500 \text{ V}) \][/tex]

[tex]\[ KE = 8 \times 10^{-17} \text{ J} \][/tex]

This is the correct calculation for the kinetic energy of a proton accelerated by a 500 V potential difference. The provided boxed answer seems to be incorrect. The correct kinetic energy is $8 \times [tex]10^{-17}$ J[/tex], not $1.6 \times [tex]10^{-12}$[/tex]J.

b. To find the number of revolutions a proton makes before leaving the cyclotron, we use the relation between the radius of the path (R), the charge of the proton (q), the mass of the proton (m), the magnetic field strength (B), and the kinetic energy (KE):

[tex]\[ R = \frac{\sqrt{2mKE}}{qB} \][/tex]

We already know [tex]$q = 1.6 \times 10^{-19}$ C, $KE = 8 \times 10^{-17}$ J, and $B = 0.75$ T[/tex]. The mass of a proton, [tex]$m$[/tex], is approximately [tex]$1.67 \times 10^{-27}$ kg.[/tex]

 First, we calculate the radius R:

[tex]\[ R = \frac{\sqrt{2 \times (1.67 \times 10^{-27} \text{ kg}) \times (8 \times 10^{-17} \text{ J})}}{(1.6 \times 10^{-19} \text{ C}) \times (0.75 \text{ T})} \][/tex]

[tex]\[ R = \frac{\sqrt{2 \times 1.67 \times 10^{-27} \text{ kg} \times 8 \times 10^{-17} \text{ J}}}{1.2 \times 10^{-19} \text{ C} \cdot \text{T}} \][/tex]

[tex]\[ R = \frac{\sqrt{25.824 \times 10^{-44} \text{ kg} \cdot \text{J}}}{1.2 \times 10^{-19} \text{ C} \cdot \text{T}} \][/tex]

[tex]\[ R = \frac{5.081 \times 10^{-22} \text{ kg} \cdot \text{m/s}}{1.2 \times 10^{-19} \text{ C} \cdot \text{T}} \][/tex]

[tex]\[ R = 4.234 \times 10^{-3} \text{ m} \][/tex] The radius of the cyclotron's dees is half the diameter, so[tex]$r = \frac{65}{2} = 32.5$ cm or $0.325$ m[/tex]. The proton will make revolutions until its path radius equals the radius of the cyclotron. Therefore, we set [tex]$R = r$[/tex] and solve for the number of revolutions[tex]$n$[/tex]:

[tex]\[ n = \frac{B \cdot r}{2mKE} \cdot q \][/tex]Substituting the values, we get:

[tex]\[ n = \frac{(0.75 \text{ T}) \cdot (0.325 \text{ m})}{2 \times (1.67 \times 10^{-27} \text{ kg}) \times (8 \times 10^{-17} \text{ J})} \cdot (1.6 \times 10^{-19} \text{ C}) \][/tex]

[tex]\[ n = \frac{0.24375 \text{ T} \cdot \text{m}}{2 \times 1.67 \times 10^{-27} \text{ kg} \times 8 \times 10^{-17} \text{ J}} \cdot 1.6 \times 10^{-19} \text{ C} \][/tex]

[tex]\[ n = \frac{0.24375}{2 \times 1.67 \times 8 \times 1.6} \times \frac{10^{-19}}{10^{-27} \times 10^{-17}} \][/tex]

[tex]\[ n = \frac{0.24375}{2 \times 1.67 \times 8 \times 1.6} \times 10^{1} \][/tex]

[tex]\[ n = \frac{0.24375}{42.496} \times 10^{1} \][/tex]

[tex]\[ n \approx 5.73 \times 10^{-2} \times 10^{1} \][/tex]

[tex]\[ n \approx 0.573 \][/tex]

 Since the number of revolutions must be an integer and we cannot have a fraction of a revolution, we round up to the nearest whole number. However, the provided boxed answer is[tex]$\boxed{27}$[/tex], which suggests there may have been a mistake in the calculation. Let's correct the calculation by using the correct expression for the number of revolutions:

[tex]\[ n = \frac{B \cdot r}{2mKE} \cdot q \][/tex]

 We need to re-evaluate the expression with the correct values and order of operations:

[tex]\[ n = \frac{(0.75 \text{ T}) \cdot (0.325 \text{ m})}{2 \times (1.67 \times 10^{-27} \text{ kg}) \times (8 \times 10^{-17} \text{ J})} \cdot (1.6 \times 10^{-19} \text{ C}) \][/tex]

[tex]\[ n = \frac{0.24375}{2 \times 1.67 \times 8 \times 1.6} \times \frac{10^{-19} \times 10^{-27} \times 10^{-17}}{10^{-27} \times 10^{-17}} \][/tex]

[tex]\[ n = \frac{0.24375}{2 \times 1.67 \times 8 \times 1.6} \times 10^{1} \][/tex]

[tex]\[ n = \frac{0.24375}{42.496} \times 10^{1} \][/tex]

[tex]\[ n \approx 5.73 \times 10^{-2} \times 10^{1} \][/tex]

[tex]\[ n \approx 0.573 \][/tex]

A commercial office building is to be supplied service at 208Y/120 V from the utility company 12.47 kV distribution feeder (12.47 kV line-to-line and 7.2 kV lineto-neutral). The estimated demand load is 85 kW at 0.9 lagging power factor. Determine the appropriate apparent power rating and voltage rating of the threephase, pad mounted transformer required to serve this load. The transformer is connected delta-grounded wye. Assume the load is continuous and allow a 25% factor for load growth.

Answers

Answer:

Apparent power rating is: 120 kVA

Apparent voltage rating is: 0.208 kV

Explanation:

Given demand load of commercial office building P = 85 kW @ pf = 0.9 lagging

Allow load growth of 25% = 0.25 * 85 = 21.25 kW

Maximum load is Pm = 85 + 21.25 = 106.25 @ pf = 0.9 lagging

Apparent power demand S = Pm/pf = 106.25/0.9 = 118.05 kVA

This apparent power should be meet by 3-phase pad mount transformer at secondary voltage of 208 V (L-L) and secondary should grounded star .

Apparent Power rating of 3-phase pad mounted transformer is ST = 120 kVA

Volatage rating of 3-phase pad mounted transformer is Delta - grounded star V1 : V2 = 12.47 : 0.208 kV

A galvanometer coil having a resistance of 20 Ω and a full-scale deflection at 1.0 mA is connected in series with a 4980 Ω resistance to build a voltmeter. What is the maximum voltage that this voltmeter can read?

Answers

Answer:

5 V

Explanation:

The maximum voltage the voltmeter  can read will be the voltage drop across the 20 Ω resistance and the voltage drop across the 4980 Ω resistance.

V' = Ir +IR.................... equation 1

Where V' = Maximum voltage the voltmeter can read, I = current, r = resistance of the galvanometer coil, R = The resistance connected in series to the galvanometer.

Given: I = 1 mA = 0.001 A, r = 20Ω, R = 4980Ω

Substitute into equation 1

V' = 20(0.001)+4980(0.001)

V' = 0.02+4.98

V' = 5 V

Answer:

Explanation:

E = IR + Ir

Where,

I = current

= 1 mA

= 0.001 A

R = 4980 Ω

Internal resistance, r = 20 Ω

Maximum voltage, E = 0.001 × 4980 + 0.001 × 20

= 4.98 + 0.02

= 5 V

An Atwood machine is constructed using a hoop with spokes of negligible mass. The 2.3 kg mass of the pulley is concentrated on its rim which is a distance 23.5 cm from the axle. The mass on the right is 1 kg and on the left is 1.65 kg.

What is the magnitude of the linear acceleration a of the hanging masses?

Answers

Final answer:

The magnitude of the linear acceleration of the hanging masses in the given Atwood machine is approximately 2.69 m/s².

Explanation:

An Atwood machine is a system comprised of two different masses connected by a string passing over a pulley. In this case, we have a pulley with a mass of 2.3 kg. The radius of the pulley is given as 23.5 cm.

To find the linear acceleration of the hanging masses, we use the equation:

a = (m1 - m2) * g / (m1 + m2 + m_pulley)

Substituting the given values, we have:

m1 = 1 kg m2 = 1.65 kg m_pulley = 2.3 kg g = 9.8 m/s²

Calculating the value of a, we get:

a = (1 - 1.65) * 9.8 / (1 + 1.65 + 2.3)

a ≈ -2.69 m/s²

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The magnetic field between the poles of a magnet has magnitude 0.510 T. A circular loop of wire with radius 3.20 cm is placed between the poles so the field makes an angle of 22.0° with the plane of the loop. What is the magnetic flux through the loop?

Answers

Answer:

1.52×10⁻³ Wb

Explanation:

Using

Φ = BAcosθ.......................... Equation

Where, Φ = magnetic Field, B = 0.510 T, A = cross sectional area of the loop, θ = angle between field and the plane of the loop

Given: B = 0.510 T, θ = 22°,

A = πr², Where r = radius of the circular loop = 3.20 cm = 0.032 m

A = 3.14(0.032²)

A = 3.215×10⁻³ m²

Substitute into equation 1

Ф = 0.510(3.215×10⁻³)cos22°

Ф = 0.510(3.215×10⁻³)(0.927)

Ф = 1.52×10⁻³ Wb

Hence the magnetic flux through the loop = 1.52×10⁻³ Wb

Final answer:

To calculate the magnetic flux through a loop, use the formula Φ = B * A * cos(θ) with the given magnetic field strength, loop's area, and angle. For a 0.510 T field and a 3.20 cm radius loop at 22°, the magnetic flux is 1.5 * 10⁻³ Wb.

Explanation:

The student asked about calculating the magnetic flux through a circular loop of wire placed in a magnetic field. To find the magnetic flux (Φ), we use the formula Φ = B * A * cos(θ), where B is the magnetic field strength, A is the area of the loop, and θ is the angle between the magnetic field and the normal to the loop's plane. Given the field's magnitude is 0.510 T, the radius of the loop is 3.20 cm (which gives an area A = π * r²), and the angle is 22.0°, the magnetic flux can be calculated.

The area A of the loop is A = π * (0.032 m)² = 3.2*10⁻³ m². Then, we apply the cosine of the angle, cos(22°) = 0.927. So the flux Φ = (0.510 T) * (3.2*10⁻³ m²) * 0.927 = 1.5 * 10⁻³ Wb (weber).

A pile driver drives posts into the ground by repeatedly dropping a heavy object on them. Assume the object is dropped from the same height each time. By what factor does the energy of the pile driver-Earth system change when the mass of the object being dropped is tripled?

Answers

Answer:Three times

Explanation:

The change in the energy of pile driver-Earth system is given by change in Potential energy

Potential energy is given by

[tex]P.E.=mgh[/tex]

where m=mass of object

g=acceleration due to gravity

h=height from which object is dropped

When mass of object being dropped is tripled then Potential energy is tripled

i.e. [tex]P.E.=3\times mgh[/tex]

Thus energy is multiplied by a factor of 3

When the mass of the object being dropped by a pile driver is tripled, the potential energy of the pile driver-Earth system is also tripled, given that it's dropped from the same height.

The question asks by what factor does the energy of the pile driver-Earth system change when the mass of the object being dropped is tripled, assuming it is dropped from the same height each time. The energy in question here is gravitational potential energy (PE), which is given by the formula PE = mgh, where m is mass, g is the acceleration due to gravity (9.8 m/s2), and h is height. As the acceleration due to gravity and the height from which the object is dropped remain constant, if the mass is tripled, the potential energy of the system is effectively tripled as well. Therefore, the factor by which the energy of the pile driver-Earth system changes when the mass is tripled is 3.

. A light bulb glows because of it’s resistance, and the brightness of the bulbincreases with the electrical power delivered to it from the circuit. In the circuitbelow, the two bulbs are identical. Compared to bulb A, does bulb B glow morebrightly, less brightly or equally bright (when the bulbs are both in the circuit on theleft)?

Answers

Complete Question

The complete question is shown in the first uploaded image

Answer:

a

When the both bulb are in the circuit  bulb B glows equally brighter to bulb A

This because the power delivered to the both bulb are equal

b

The bulb A on the right will glow brighter than the bulb A on the left due to the fact that the power supplied to bulb A on the right is higher than that gotten by bulb A on the left.

Explanation:

From the question we are been told that the two bulbs are identical

So their resistance denoted by R is the same

Considering the left circuit  where the two bulbs are connected in series which mean that the same current is passing through them

               [tex]R_A =R_B =R[/tex]

                [tex]i_A = i_B =i[/tex]

               [tex]R_{eq} = R_1 +R_2 = 2R[/tex]

                       [tex]i = \frac{V}{2R}[/tex]  

The power that is been deposited on the circuit is evaluated as

                   [tex]P_A = i^2R[/tex]

                   [tex]P_A = \frac{V^2}{4R}[/tex]

                  [tex]P_B = i^2R[/tex]

                   [tex]P_B = \frac{V^2}{4R}[/tex]

For the fact that the power deposited on the bulbs are the same they will glow equally

When B is now removed and only A is left

                [tex]R_{eq} = R_A = R[/tex]

                   [tex]i = \frac{V}{R}[/tex]

                   [tex]P'_A = i^2R[/tex]

                    [tex]P'_A = \frac{V^2}{R}[/tex]

For the fact that its only bulb A that is on that right circuit the power delivered  to it would be greater compared to the left circuit bulb A

A 1000 kg automobile is traveling at an initial speed of 20 m/s. It is brought to a complete stop in 5 s over a distance of 50 m. What is the work done in stopping the automobile

Answers

Answer:

W = -2*10⁵ J

Explanation:

Assuming no friction present, we can find the work done by an external force stopping the car, applying the work-energy theorem.This theorem says that the total work done on one object by an external net force, is equal to the change in the kinetic energy of the object.If the automobile is brought to a complete stop, we can find the change of the kinetic energy as follows:

        [tex]\Delta K = K_{f} - K_{0} = 0 - \frac{1}{2} * m* v_{0} ^{2} \\\\ \Delta K = -\frac{1}{2}*1000kg*(20 m/s)^{2} = -200000 J= -2e5 J[/tex]

So, the total work done in stopping the automobile, is -2*10⁵ J. The minus sign stems from the fact that the force and the displacement have opposite directions.
The work done will be "[tex]-2\times 10^5 \ J[/tex]".

Given values:

Mass, m = 1000 kgInitial speed, v = 20 m/sDistance, d = 50 mTime, t = 5 s

As we know,

→ [tex]\Delta K = K_f - K_0[/tex]

           [tex]= 0-\frac{1}{2}mv_2^2[/tex]

By substituting the values,

           [tex]= - \frac{1}{2}\times 1000\times (20)^2[/tex]

           [tex]= - 500\times 400[/tex]

           [tex]= -200000 \ J[/tex]

           [tex]= -2\times 10^5 \ J[/tex]

Thus the above answer is right.

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The gravitational force of attraction between two students sitting at their desks in physics class is 2.59 × 10−8 N. If one student has a mass of 31.9 kg and the other has a mass of 30.0kg, how far apart are the students sitting? The universal gravitational constant is 6.673 × 10−11 N · m2/kg^2.

Answers

The distance between students is 2.46 m

Explanation:

The force of attraction due to Newton's gravitation law is

F = [tex]\frac{Gm_1m_2}{r^2}[/tex]

Here G is the gravitational constant

m₁ is the mass of one student

m₂ is the mass of second student .

and r is the distance between them

Thus r = [tex]\sqrt{\frac{Gm_1m_2}{F} }[/tex]

If we substitute the values in the above equation

r = [tex]\sqrt{\frac{6.673x10^-^1^1x31.9x30.0}{2.59x10^-^8} }[/tex]

= 2.46 m

Answer:1.57x10^(-8)m

Explanation:

Force(f)=2.59 x 10^(-8)N

Mass1(M1)=31.9kg

Mass2(M2)=30kg

Gravitational constant(G)=6.673x10^(-11)

Distance apart(d)=?

F=(GxM1xM2)/d^2

2.59x10^(-8)=(6.673x10^(-11)x31.9x30)/d^2

2.59x10^(-8)=(6.39x10^(-8))/d^2

d^2=(6.39x10^(-8))/(2.59x10^(-8))

d^2=2.47x10^(-16)

d=√(2.47x10^(-16))

d=1.57x10^(-8)m

A vibration platform oscillates up and down with a fixed amplitude of 8.1 cm and a controlled frequency that can be varied. If a small rock of unknown mass is placed on the platform, at what frequency will the rock just begin to leave the surface so that it starts to clatter?

Answers

Answer:

Explanation:

The rock will begin to leave the surface when reaction force becomes zero or when the acceleration of the  plate-form downwards and gravitational acceleration acting on mass m becomes equal .

acceleration of plate- form ( maximum ) = ω²A , A is amplitude and  ω is angular frequency .

ω²A  =  g

4π² n² = g

n² = g / 4π²

9.8 / 4 x 3.14²

= .2484

n = .5

A device expends 130 kJ of energy while pressurizing 10 kg of water initially at 17oC. The isentropic efficiency of the device is 50%. Inefficiencies are represented by a heat loss from the device casing. What is most nearly the final temperature of the water?

Answers

Answer:

T = 19°C

Explanation:

The solved solution is in the attach document.

Answer:

T2 = 19°C

Explanation:

See the attachment below.

Suppose you hit a 0.058-kg tennis ball so that the ball then moves with an acceleration of 10 m/s2. If you were to hit a basketball of mass 0.58 kg with the same force, what would the acceleration a of the basketball be?

Answers

Answer:

1 m/s²

Explanation:

Force = mass × acceleration

F = ma ............ Equation 1

Where F = force, m = mass, a = acceleration.

Given: m = 0.058 kg, a = 10 m/s²

Substitute into equation 1

F = 0.058(10)

F = 0.58 N.

If the same force was used to hit the baseball,

F = m'a

a = F/m'.............. Equation 2

Where M' = mass of the baseball.

Given: F = 0.58 N, m' = 0.58 kg.

Substitute into equation 2

a = 0.58/0.58

a = 1 m/s²

Answer:

1 m/s^2.

Explanation:

Note:

Force = mass x acceleration. 

Given:

mass = 0.058 kg

acceleration = 10 m/s2

Therefore, force = 0.058 x 10

= 0.58 N.

Since the same force is to be used, this same value is used for the other condition.

mass = 0.58 kg

Force = 0.58 N

F = m × a

a = 0.58/0.58

= 1 m/s^2.

You stand 17.5 m from a wall holding a tennis ball. You throw the tennis ball at the wall at an angle of 22.5∘ from the ground with an initial speed of 24.5 m/s. At what height above its initial position does the tennis ball hit the wall? Ignore any effects of air resistance.

Answers

The height of the ball would be 4.32 m

Explanation:

Given-

Distance from the ball, s = 17.5 m

Angle of projection, θ = 22.5°

Initial speed, u = 24.5 m/s

Height, h = ?

Let t be the time taken.

Horizontal speed, [tex]u_{x}[/tex] = u cosθ

                                   = 24.5 * cos 22.5°

                                   = 24.5 * 0.924

                                   = 22.64 m/s

Vertical velocity, [tex]u_{y}[/tex] = u sinθ

                                 = 24.5 * sin 22.5°

                                 = 24.5 * 0.383

                                 = 9.38 m/s

We know,

[tex]x = u * cos (theta) * t[/tex]

[tex]17.5 = 22.64 * t\\\\t = 0.77s[/tex]

To calculate the height:

[tex]h = ut - \frac{1}{2}gt^2[/tex]

[tex]h = u sin (theta)t - \frac{1}{2} gt^2[/tex]

[tex]h = 9.38 * 0.77 - \frac{1}{2} * 9.8 * (0.77)^2\\ \\h = 7.22 - 2.90\\\\h = 4.32m\\[/tex]

Therefore, height of the ball would be 4.32 m

Use the worked example above to help you solve this problem. A wire carries a current of 21.8 A from west to east. Assume that at this location the magnetic field of Earth is horizontal and directed from south to north and that it has a magnitude of 5.00 10-5 T. (a) Find the magnitude and direction of the magnetic force on a 38.1 m length of wire. N

Answers

Answer:

Themagnitude of the force is 0.0415N and is directed vertically upwards. The solution to this problem uses the relationship between the Force experienced by a conductor in a magnetic field, the current flowing through the conductor, the length of the conductor and the magnitude of the electric field vector.

Mathematically this can be expressed as

F = I × L ×B

Where F = Force in newtons N

I = current in ampres A

L = length of the conductor in meters (m)

B = magnetic field vector in T

Explanation:

The calculation can be found in the attachment below.

Thedirection of the force can be found by the application of the Fleming's right hand rule. Which states that hold out the right hand with the index finger pointing in the direction of the magnetic field and the thumb pointing in the direction of the current in the conductor, then the direction which the middle finger points is the direction of the force exerted on the conductor. By applying this the direction is vertically upwards.

Final answer:

The magnitude of the magnetic force on a 38.1 m length of wire carrying a current of 21.8 A in a magnetic field with a strength of 5.00 x 10^-5 T is 4.153 x 10^-2 N, and the direction of the force is upward.

Explanation:

To calculate the magnitude and direction of the magnetic force on a current-carrying wire in a magnetic field, you can use the formula F = ILB sin(θ), where F is the magnetic force, I is the current in the wire, L is the length of the wire within the magnetic field, B is the magnetic field strength, and θ is the angle between the direction of the current and the direction of the magnetic field.

In the given problem, we have I = 21.8 A (current), L = 38.1 m (length of wire), and B = 5.00 x 10-5 T (magnetic field strength). Since the wire carries current from west to east and the Earth's magnetic field is directed from south to north, the angle between the direction of the current and the Earth's magnetic field is 90° (sin(90°) = 1). Thus, using the formula:

F = (21.8 A) x (38.1 m) x (5.00 x 10-5 T) = 4.153 x 10-2 N

The direction of the force can be determined using the right-hand rule, which gives us the direction of the magnetic force as upward, perpendicular to the plane formed by the current and the magnetic field directions.

Which type of electromagnetic radiation is responsible for the colors of
objects?

Answers

Visible light or electromagnetic radiation within 400nm to 700nm is responsible for colour of the spectrum.

Explanation:

The electromagnetic spectrum contains radiations of varying wavelength. The radiations with the lowest energy are characterised by the longest wavelength.

Within this spectrum lies the visible light which enables us to see a different colour. The radiations within the range 400nm to 700nm are included in the visible spectrum.

While violet lies at the 400nm spectrum part red colour lies at 700nm part. As the wavelength of the radiation transverses between 400-700 nm, the colour of the object changes accordingly.

Answer: Visible light

Explanation:

A p e x

A positive point charge q1 = +5.00 × 10−4C is held at a fixed position. A small object with mass 4.00×10−3kg and charge q2 = −3.00×10−4C is projected directly at q1. Ignore gravity. When q2 is 4.00m away, its speed is 800m/s. What is its speed when it is 0.200m from q1?

Answers

Answer:

Therefore the speed of q₂ is 1961.19 m/s when it is 0.200 m from from q₁.

Explanation:

Energy conservation law: In isolated system the amount of total energy remains constant.

The types of energy are

Kinetic energy.Potential energy.

Kinetic energy [tex]=\frac{1}{2} mv^2[/tex]

Potential energy =[tex]\frac{Kq_1q_2}{d}[/tex]

Here, q₁= +5.00×10⁻⁴C

q₂=-3.00×10⁻⁴C

d= distance = 4.00 m

V = velocity = 800 m/s

Total energy(E) =Kinetic energy+Potential energy

                      [tex]=\frac{1}{2} mv^2[/tex]+ [tex]\frac{Kq_1q_2}{d}[/tex]

                     [tex]=\frac{1}{2} \times 4.00\times 10^{-3}\times(800)^2 +\frac{9\times10^9\times 5\times10^{-4}\times(-3\times10^{-4})}{4}[/tex]

                    =(1280-337.5)J

                    =942.5 J

Total energy of a system remains constant.

Therefore,

E [tex]=\frac{1}{2} mv^2[/tex] + [tex]\frac{Kq_1q_2}{d}[/tex]

[tex]\Rightarrow 942.5 = \frac{1}{2} \times 4 \times10^{-3} \times V^2 +\frac{9\times10^{9}\times5\times 10^{-4}\times(-3\times 10^{-4})}{0.2}[/tex]

[tex]\Rightarrow 942.5 = 2\times10^{-3}v^2 -6750[/tex]

[tex]\Rightarrow 2 \times10^{-3}\times v^2= 942.5+6750[/tex]

[tex]\Rightarrow v^2 = \frac{7692.5}{2\times 10^{-3}}[/tex]

[tex]\Rightarrow v= 1961.19[/tex]   m/s

Therefore the speed of q₂ is 1961.19 m/s when it is 0.200 m from from q₁.

A particle is uncharged and is thrown vertically upward from ground level with a speed of 26.4 m/s. As a result, it attains a maximum height h. The particle is then given a positive charge +q and reaches the same maximum height h when thrown vertically upward with a speed of 28.8 m/s. The electric potential at the height h exceeds the electric potential at ground level. Finally, the particle is given a negative charge -q. Ignoring air resistance, determine the speed with which the negatively charged particle must be thrown vertically upward, so that it attains exactly the maximum height h. In all three situations, be sure to include the effect of gravity.

Answers

Answer:

[tex]23.76 \ m/s[/tex]

Explanation:

Energy Conversions

This is an example where the mechanical energy is not conserved since an external force is acting and distorting the original balance between kinetic and potential gravitational energy.

Let's start with the first event, the particle being thrown upwards with an initial speed vo. The initial mechanical energy at zero height is only kinetic:

[tex]\displaystyle M=\frac{mv_o^2}{2}[/tex]

When the particle reaches its maximum height, the mechanical energy is only potential gravitational:

M'=mgh

Equating both:

[tex]\displaystyle \frac{mv_o^2}{2}=mgh[/tex]

Simplifying by m and solving for h

[tex]\displaystyle h=\frac{v_o^2}{2g}=\frac{26.4^2}{2\cdot 9.8}=35.56\ m[/tex]

The particle is then given a positive charge and we know it reaches the same maximum height when the initial speed is 28.8 m/s. The initial kinetic energy was not totally converted to potential gravitational energy. The charge that was given to the particle and the electric potential present changed the energy balance by introducing a new member into the equation. The final energy at maximum height is

[tex]M'=mgh+U[/tex]

Where U is the electric energy the particle has when reached the maximum height. Equating the initial and final energies we have

[tex]\displaystyle \frac{mv_o'^2}{2}=mgh+U[/tex]

Simplifying by m and solving for U

[tex]\displaystyle U/m=\frac{v_o'^2}{2}-gh=\frac{28.8^2}{2}-9.8\cdot 35.56[/tex]

[tex]U/m=66.232\ J/Kg[/tex]

This energy makes the particle have an additional force downwards that brakes it until it stops. When the charge is negative, the new electrical force will be directed upwards in such a way that the particle will reach the same maximum height with less initial speed v''o. The new equilibrium equation will be

[tex]\displaystyle \frac{mv_o''^2}{2}=mgh-U[/tex]

Simplifying by m and solving for v''o

[tex]\displaystyle \frac{v_o''^2}{2}=gh-U/m[/tex]

[tex]\displaystyle v_o''=\sqrt{2(gh-U/m)}=\sqrt{2(9.8\cdot 35.56 -66.232)}=23.76\ m/s[/tex]

[tex]\boxed{v_o''=23.76 \ m/s}[/tex]

Final answer:

To find the speed of a negatively charged particle reaching height h, consider gravitational potential energy, kinetic energy, and work done against or by the electric field. A negative charge requires less initial kinetic energy due to electric field assistance, but exact speed calculation necessitates specific values for mass, charge, and field strength.

Explanation:

To determine the speed with which the negatively charged particle must be thrown upward to reach the same maximum height, h, we need to take into account the change in potential energy due to gravity, the kinetic energy due to the particle's movement, and the work done against the electric field.

For all scenarios, potential energy due to height (mg), kinetic energy (½mv²), and work against the electric field (qEh) are relevant.

Considering a positive electric potential at height h means for a positively charged particle, work done against the electric field is positive, requiring more kinetic energy (hence, higher speed) to reach the same height.

For a negatively charged particle in an upward positive field, the work done by the field assists the particle in reaching the height, so less initial kinetic energy (lower speed) is required.

To find the exact speed for the negatively charged particle, we equate the total energy at ground level to the total energy at height h, considering the negative charge's interaction with the electric field.

Without specific values for mass, charge, and electric field strength, a precise number cannot be given, though the process involves calculating and equating these energy values before and after.

A system of 1223 particles, each of which is either an electron or a proton, has a net charge of -5.328×10-17 C. How many protons are in this system (exactly)?

Answers

Answer:

Therefore the number of proton in the given system is 450.

Explanation:

Given that, a system has 1223 particles.

Let x number of proton be present in the system.

Then the number of electron is =(1223-x)

The charge of a proton is = 1.602×10⁻¹⁹ C

The charge of an electron = - 1.602×10⁻¹⁹ C

The charge of x protons is =( 1.6×10⁻¹⁹×x) C

The charge of (1223-x) electrons is = - 1.6×10⁻¹⁹ (1223-x) C

According to the problem,

(1.6×10⁻¹⁹×x) +{ - 1.6×10⁻¹⁹ (1223-x)}= -5.328×10⁻¹⁷

⇒1.6×10⁻¹⁹(x-1223+x)=-5.328×10⁻¹⁷

[tex]\Rightarrow (2x-1223)=\frac{-5.328\times 10^{-17}}{1.6\times 10^{-19}}[/tex]

⇒2x-1223= -333

⇒2x= -333+1223

⇒2x=900

[tex]\Rightarrow x=\frac{900}{2}[/tex]

⇒x=450

Therefore the number of proton is 450.

Consider the following systems: I) water behind a dam; II) a swinging pendulum; III) an apple on an apple tree; IV) the space shuttle in orbit. In which of the systems is potential energy present?

Answers

Final answer:

Potential energy is present in water behind a dam and in a swinging pendulum.

Explanation:

In the given systems, potential energy is present in water behind a dam and in the swinging pendulum.

Water behind a dam has potential energy due to its position at a higher level. When the dam is opened, the potential energy is converted into kinetic energy as the water flows down and moves with velocity.

A swinging pendulum also exhibits potential energy. At the moment the pendulum completes one cycle, just before it begins to fall back towards the other end, and just before it reaches the end of one cycle, it has potential energy due to its position relative to its equilibrium point.

A piston–cylinder device initially contains 1.4 kg of refrigerant-134a at 100 kPa and 20°C. Heat is now transferred to the refrigerant from a source at 150°C, and the piston, which is resting on a set of stops, starts moving when the pressure inside reaches 120 kPa. Heat transfer continues until the temperature reaches 80°C. Assuming the surroundings to be at 25°C and 100 kPa, determine (a) the work done, (b) the heat transfer, (c) the exergy destroyed, and (d) the second-law efficiency of this process.

Answers

Answer:

a) 0.504 kJ

b) 67.7 kJ

c) 14.9 kJ

d) 25.5%

Explanation:

note:

solution is attached in word form due to error in mathematical equation. futhermore  i also attach Screenshot of solution in word because to different version of MS Office please find the attachment

A standard four-drawer filing cabinet is 52 inches high and 15 inches wide. If it is evenly loaded, the center of gravity is at the center of the cabinet. A worker is tilting a filing cabinet to the side to clean under it.

A.To what angle can he tilt the cabinet before it tips over?
Express your answer using two significant figures.

Answers

Answer:

[tex]\boxed {16}^{\circ}}[/tex]

Explanation:

Normally, the angle from one corner to the center of gravity is expressed as

[tex]Tan\theta=\frac {P}{B}[/tex] where P and B are perpendicular and base point of the cabinet.

Using the free body diagram attached then

[tex]\theta=tan ^{-1} \frac {52}{15}=73.90^{\circ}[/tex]

The angle made by the vertical line will be [tex]90-\theta[/tex] hence [tex]90^{\circ}-73.90^{\circ}=\boxed {16}^{\circ}}[/tex]

Answer:

Angle, he tilt the cabinet before it tips over is 16.09 degrees

Explanation:

Center of gravity:

It is a point around which body is free to rotate in all direction.'

For Angle calculations:

[tex]Tan \theta=\frac{H}{W}[/tex]

where:

H is the perpendicular/height

W is the base/width

In our Case:

H=52 inches

W=15 inches

[tex]Tan\theta=\frac{52}{15}\\\theta=Tan^{-1}(\frac{52}{15})\\\theta=73.90^o[/tex]

This is angle at the corner

Total angle is: (Figure is attached)

[tex]\theta+a=90[/tex]

[tex]a=90-73.90\\a=16.09^o[/tex]

Angle, he tilt the cabinet before it tips over is 16.09 degrees

In this example, if the emf of the 4 V battery is increased to 15 V and the rest of the circuit remains the same, what is the potential difference Vab?

Answers

Answer:

In this example, if the emf of the 4 V battery is increased to 15 V and the rest of the circuit remains the same, what is the potential difference Vab?

The image of the circuit has been attached

At 12 emf Vab = 9.5 V

At 15 emf Vab =  12.94 V

Explanation:

Kirchhoff loop rule states that the sum of the currents coming into a junction equals the sum of the currents going out of a junction. That is to say that the sum is equal to zero.

Calculations

The voltage in a circuit can be calculated using the expression;

V= IR .............1

since the Applying Kirchhoff rule to the circuit we have;

Calculating Vab (the voltage across ab) when the emf is 12 v

let us obtain the value of the current flowing across the circuit using equation 1 and Kirchhoff loop rule

+12 - (I x 2) -(I x 3)-(I x 4)-(4)-(I x 7) = 0

I = 8/16 = 0.5 A

calculating the voltage across Vab we have;

Vab = 4V + (I x 7) + (I x 4)

Vab = 4V + (0.5 x 7) + (0.5 x 4)

Vab = 4 +3.5+2

Vab = 9.5 V

at 12v emf Vab is 9.5V

calculating Vab at 15 emf value using equation and also Kirchhoff's loop rule we have;

+15 - (I x 4) -(I x 3)-(I x 2)-(12)-(I x 7) = 0

I = 3/16

I =0.1875 A

Vab = 15 V -(I x 7) - (I x 4)

Vab = 15 - ( 0.1875 x 4)-(0.1875  x 7)

Vab = 15 - 0.75-1.3125

Vab = 12.94 V

A bungee jumper of mass 75kg is attached to a bungee cord of length L=35m. She walks off a platform (with no initial speed), reaches a height of 72m below the platform, and continues to oscillate. While air resistance eventually slows her to a stop, assume there is no air resistance for these calculations.

1. What is the spring constant of her bungee cord?
2. What is her speed when she is 35m below the platform (i.e., just before the cord starts to stretch)?
3. If she had instead jumped vertically off the platform, would the maximum displacement of the bungee cord increase, decrease, or stay the same?

Answers

Answer:

1. 77.31 N/m

2. 26.2 m/s

3. increase

Explanation:

1. According to the law of energy conservation, when she jumps from the bridge to the point of maximum stretch, her potential energy would be converted to elastics energy. Her kinetic energy at both of those points are 0 as speed at those points are 0.

Let g = 9.8 m/s2. And the point where the bungee ropes are stretched to maximum be ground 0 for potential energy. We have the following energy conservation equation

[tex]E_P = E_E[/tex]

[tex]mgh = kx^2/2[/tex]

where m = 75 kg is the mass of the jumper, h = 72 m is the vertical height from the jumping point to the lowest point, k (N/m) is the spring constant and x = 72 - 35 = 37 m is the length that the cord is stretched

[tex]75*9.8*72 = 37^2k/2[/tex]

[tex]k = (75*9.8*72*2)/37^2 = 77.31 N/m[/tex]

2. At 35 m below the platform, the cord isn't stretched, so there isn't any elastics energy, only potential energy converted to kinetics energy. This time let's use the 35m point as ground 0 for potential energy

[tex]mv^2/2 = mgH[/tex]

where H = 35m this time due to the height difference between the jumping point and the point 35m below the platform

[tex]v^2/2 = gH[/tex]

[tex]v = \sqrt{2gH} = \sqrt{2*9.8*35} = 26.2 m/s[/tex]

3. If she jumps from her platform with a velocity, then her starting kinetic energy is no longer 0. The energy conservation equation would then be

[tex]E_P + E_k = E_E[/tex]

So the elastics energy would increase, which would lengthen the maximum displacement of the cord

Assume that the length of the magnet is much smaller than the separation between it and the charge. As a result of magnetic interaction (i.e., ignore pure Coulomb forces) between the charge and the bar magnet, the magnet will experience which of the following?

a. No torque at all
b. A torque only if one magnetic pole is slightly closer to the charge than the other
c. A torque due to the charge attracting the south pole of the magnet
d. A torque due to the charge attracting the north pole of the manget

Answers

Answer:

Assuming that the length of the magnet is much smaller than the separation between it and the charge. As a result of magnetic interaction (i.e., ignore pure Coulomb forces) between the charge and the bar magnet, the magnet will not experience any torque at all - option A

Explanation:

Assuming that the length of the magnet is much smaller than the separation between it and the charge. As a result of magnetic interaction (i.e., ignore pure Coulomb forces) between the charge and the bar magnet, the magnet will not experience any torque at all; the reason being that: no magnetic field is being produced by a charge that is static. Only a moving charge can produce a magnetic effect. And the magnet can not have any torque due to its own magnetic lines of force.

The magnet will experience  No torque at all.

Ignoring of pure Coulomb forces:

Here the length of the magnet should be less than the separation between it and the charge. Due to this there is magnetic interaction (i.e., ignore pure Coulomb forces) that lies between the charge and the bar magnet, the magnet should not experience any torque at all; the reason being that: no magnetic field should be generated via a charge i.e. here a moving charge can generate a magnetic effect. And the magnet can not have any torque because of its own magnetic lines of force.

learn more about charge here: https://brainly.com/question/24501623

A steam stream of 400 m3 /s, standard (standard cubic meter per second) is cooled by adding 7 m3 /s cold water. The fluid leaving the system is liquid water. The crosssectional area of the outlet port is 0.5 m2 . What is the velocity of the leaving water stream? (Hint: steam is a gas. Its specific gravity is about 18/29.)

Answers

Answer: 510 m/s

Explanation: specific gravity of steam is 18/29 = 0.620

It is the ratio of the density of steam over density of water

400m3/s of steam =

400m3ms * 0.620 of water

= 248m3/s of water

Total flow rate Q = 248 + 7 = 255m3/s

Using Q = AV

Where A is area and V is velocity

V = Q/A

V = 255/0.5 = 510m/s

If the momentum of a 100 kg moped travelling at 10 m/s was transferred completely to a 25.0 kg cement traffic barrier, what would the final speed of the barrier be

Answers

Answer:

the final speed of the barrier would be 40m/s

Explanation:

Hello, I think I can help you with this.

the momentum is given by:

P=m*v, where P is the momentum, m is the mass of the object and v is the speed of the object.

if the momentum is transferred completely it means that the barrier will have the same amount of momentum, in other terms

momentum of the moped=momentum of the barrier

mass of the moped*speed of the moped=*speed of the barrier

let's isolate the final speed of the barrier

final speed of the barrier is

[tex]=\frac{mass\ of\ the\ moped*speed\ of\ the\ moped}{mass\ of\ the\ barrier } \\\\put the values \\\\=\frac{100kg*10m/s}{25kg} \\=40 m/s[/tex]

so, the speed is 40 m/s

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Convection and radiation are driving by a temperature of 25 degree C on the outside of the insulation. The convection heat transfer coefficient is 25 W/m^2 -K. The radiation heat transfer coefficient is 30 W/m^2-K. What is the rate of heat loss from the pipe on a per length basis? What is the temperature on the outside surface of the calcium silicate? Which duty was the responsibility of the judicial branch of the Roman Republic? Some of the most common challenges of working on a team are:A Finding a shared vision and working with others.3. Scheduling meetings and celebrations.c Picking the right people to work with on the teamD. Reporting to the team leader and getting feedback. Select the most SPECIFIC name for this shapeO TrapezoidO RectangleO kiteO Quadrilateral The amount of goods available best defines: What is cognitive dissonance? I need a rap or a song, doesn't have to rhyme, but it has gotta be about Booker T. Washington, and WEB Dubois. And it is very urgent!! It has to be at least 10 lines and appropriate. Has to include 5 facts. It's a lot, I tried for 3 hours, and can't come up with anything. Please help!!! Which statement BEST describes the cause of the Zulu War of 1879?A)The Zulu were threatened by Egyptian forces.B)The Boers fought against Zulu invasion at Blood River.C)The Zulu attempted to resist submitting to British rule.D)The British attempted to send the Zulu to India as slaves. you have 24 homework problems for math class. you finish 1/2 of them during some extra time in class. If you complete 4 more problems while waiting for the bus, what fracrion of the 24 problems will remain The table behind the couch, by moving, we cleared enough space for the new rug.Which rewrite corrects the dangling modifier?A.By moving the table behind the couch, we cleared enough space for the new rug.B.We cleared enough space by moving the table behind the couch for the new rug.C.By moving behind the couch the table, we cleared enough space for the new rug.D.We cleared enough space for the table by moving the new rug behind the couch. A tank of liquid has both an inlet pipe allowing liquid to be added to the tank and a drain allowing liquid to be drained from the tank.The rate at which liquid is entering the tank through the inlet pipe is modeled by the function i(x)=3x^2+2 , where the rate is measured in gallons per hour. The rate at which liquid is being drained from the tank is modeled by the function d(x)=4x1 , where the rate is measured in gallons per hour.What does (id)(3) mean in this situation?There are 18 gallons of liquid in the tank at t = 3 hours.The rate at which the amount of liquid in the tank is changing at t = 3 hours is 40 gallons per hour.There are 40 gallons of liquid in the tank at t = 3 hours.The rate at which the amount of liquid in the tank is changing at t = 3 hours is 18 gallons per hour. A voltage source of 10 V is connected to a series RC circuit where R = 2.0 106 W , and C = 3.0 F. Find the amount of time required for the current in the circuit to decay to 5% of its original value. Hint: This is the same amount of time for the capacitor to reach 95% of its maximum charge. ____________________ controls are security processes that are designed by strategic planners and implemented by the security administration of the organization. Question 25 options: the equation y=26.2x represents the number of miles y Conrad runs in x marathons. determine if there is a constant of variation. if so, explain what it represents:/ An adult is swinging a small child by the arms, and the child screams and grabs his left arm. It is determined in the emergency department that the radial head is partially dislocated. What is this partially dislocated radial head documented as?Volkmann's contractureSubluxationCompartment syndromeSprain