A train traveling at 50 miles per hour has to slow down to 10 miles per hour in 4 seconds. What is the acceleration

Answer:

B. $4,000

Explanation:

The formula for the simple interest is

[tex]interest = P\cdot r \cdot t[/tex]

where

P is the principal

r is the interest rate

t is the number of years

In this problem,

P = 20,000 $

r = 0.05

t = 4 years

So the interest is

[tex]P=(20,000 $)(0.05 )(4)=4,000 $[/tex]

Answer:

The force of the man pushing on the handle

Explanation:

The man pushing the cart is the main and only way the cart will move. If he didn't push it, he cart would just come to a halt....

It's A, The force of the man pushing on the handle

Answer:

A. sara is correct. IMA = length/height

Explanation:

Answer:

The longer the ramp, the greater the AMA.

Explanation:

When you are creating devices, mechanical devices like ramps to make a job easier for the human being, you want to create them as efficient and with the most upside possible, in that case when building a ramp the longer the ramp the easier it is to push something upwards on it, because the weight of the object is less taken into consideration as the angle of the ramp becomes smaller.

A) [tex]0.048 v_0[/tex]

The law of conservation of momentum states that the total initial momentum must be equal to the total final momentum, so

[tex]p_i = p_f\\m v_0 = (m+M)v[/tex]

where

m = 50 g = 0.05 kg is the mass of the ball

v0 is the initial speed of the ball

M = 1.0 kg is the mass of the block

v is the final speed of the block+ball together

Solving for v, we find

[tex]v=\frac{mv_0}{m+M}=\frac{(0.05 kg)v_0}{0.05 kg+1.0 kg}=0.048 v_0[/tex]

B) 95.2 %

The initial kinetic energy of the ball is:

[tex]K_i=\frac{1}{2}mv_0^2 = \frac{1}{2}(0.05 kg)v_0^2 = 0.0250 v_0^2[/tex]

while the final kinetic energy of the system is

[tex]K_f=\frac{1}{2}(m+M)v^2 = \frac{1}{2}(0.05 kg+1.0 kg)(0.048 v_0)^2 = 0.0012 v_0^2[/tex]

So, the loss in kinetic energy is

[tex]\Delta K=K_i - K_f = 0.0250 v_0^2 - 0.0012 v_0 ^2 =0.0238 v_0^2[/tex]

In percentage,

[tex]\frac{\Delta K}{K_i}=\frac{0.0238 v_0^2}{0.0250 v_0^2}=0.952[/tex]

which means 95.2%.

Answer:

5. Speed

Explanation:

Any object in free fall in a vacuum has the same acceleration towards the ground, called acceleration of gravity:

g = 9.8 m/s^2

This means that the speed of an object in free-fall is always given by the equation

v = u +gt (1)

where u is the initial speed and t is the time.

In this case, both balls start from rest (u=0). Since they have same acceleration, they will cover the same distance, 1 m, in the same time t: this means that according to (1), they will also have same speed.

All the other options listed are wrong since they all depend on the mass of the object, and in this case the two objects have different mass.

Answer:

Balanced Forces

Explanation:

Balanced forces do not cause a change in the motion of objects. Forces that cause a change in motion of objects are called unbalanced forces. Unbalanced forces can change the motion of an object in two ways.

Forces that are equal in size but opposite in direction are called balanced forces. Balanced forces do not cause a change in the motion of objects. Forces that cause a change in motion of objects are called unbalanced forces. Unbalanced forces can change the motion of an object in two ways.

Answer:

C. Different levels of sunlight at different latitudes

Explanation:

If we take the arrangement of the climate types on Earth, we can easily notice that they are arranged roughly by latitude. The tropical climates are in the lower latitudes, the temperature climates are in the mid-latitudes, while the polar climates are in the high latitudes. The reason for this is that the sunlight doesn't heat every part of the Earth equally. The low latitudes are receiving sunlight at a direct or close to direct angle, thus the sunlight is more concentrated and they are warm.hot all year round. Because of the tilting of the Earth, and because of the rounded shape of it, the sunlight falls at smaller angle in the mid-latitudes, with changes of the angle of fall throughout the year, so there's seasons with drastically different weather conditions. The high latitudes receive sunlight at a very low angle, resulting in dispersal of the sunlight on much greater area, thus heating up the surface very little,. resulting in very cold weather conditions.

Answer:

running and not stopping at traffic lights and stop signs

Explanation:

Stopping the vehicle at traffic lights and stop signs are most important to avid any accidents or collisions. Traffic lights and signs  are meant to control the traffic and avoid any collision. It allows and helps to pass the vehicles to drive away safely. But not following the traffic signs and not stopping at the traffic lights can lead to fatal accidents and serious injuries. This is very dangerous and must be avoided.

The top five contributing risk factors to fatal crashes in Texas are: speeding, driving under the influence, failure to control speed, failure to drive in a single lane, and distraction or inattention.

To understand why this is the correct answer, one must consider the common risk factors that contribute to fatal crashes not only in Texas but in many other places as well. The top five contributing risk factors to fatal crashes often include:

 1. Speeding: Exceeding the speed limit or driving too fast for conditions is a major contributing factor to fatal crashes. Speeding reduces the driver's ability to react to sudden changes in the road environment and increases the severity of a crash.

 2. Driving Under the Influence: Operating a vehicle under the influence of alcohol or drugs impairs a driver's judgment, coordination, and reaction time, leading to a higher risk of accidents, including fatal ones.

 3. Failure to Control Speed: This is related to speeding but focuses on the driver's inability to adjust their speed to the traffic, road conditions, or weather, leading to loss of vehicle control and crashes.

 4. Failure to Drive in a Single Lane: This risk factor includes behaviors such as weaving in and out of traffic, drifting out of one's lane, or making unsafe lane changes, which can result in head-on collisions or sideswipe accidents.

 5. Distraction or Inattention: Distracted driving involves any activity that diverts a driver's attention from the primary task of driving. This includes texting, talking on the phone, eating, drinking, talking to passengers, or any other form of distraction. Inattention can also be due to daydreaming or simply not paying enough attention to the road and surrounding conditions.

 These five risk factors are frequently cited in traffic safety reports and studies as the leading causes of fatal crashes. Distraction or inattention is particularly notable because it encompasses a wide range of behaviors that can take a driver's focus away from the task of driving, thus increasing the likelihood of a fatal crash."

Answer:

A. 40 cm

Explanation:

For a curved mirror, the focal length is twice the radius of curvature of the mirror. In formula:

[tex]f=2R[/tex]

where

f is the focal length

R is the radius of curvature

The concave mirror in this problem has a radius of curvature of

R = 20 cm

so, its focal length is

[tex]f=2R=2(20 cm)=40 cm[/tex]

Answer:

y = 12,000x + 40,000

Explanation:

A linear relationship that would model the mileage of the car in this example is:

[tex]y=mx+q[/tex]

where

y is the number of miles

x is the number of years

m is the number of miles driven per year

q is the number of miles already in the car at x=0

In this problem, we have

m = 12,000 (number of miles driven per year)

q = 40,000 (number of miles already in the car at x=0)

So substituting into the equation we get

[tex]y=12,000 x + 40,000[/tex]

Answer:

Notice that many plate boundaries do not coincide with coastlines. Earthquakes can also occur far from the edges of plates, along faults. Faults are cracks in the earth where sections of a plate (or two plates) are moving in different directions. Faults are caused by all that bumping and sliding the plates do.

Mercury.

On the side that is facing sun it's extremely hot.

On the other side it's extremely cold.

Hope this helps.

r3t40

Answer: C - 60km !!!

Explanation:

Answer:

Venus

Explanation:

Venus is the second plate in the solar system. It is a terrestrial planet and it is part of the inner rocky planets.

In Venus, it rains sulfuric acid but the rain never reaches the surface before it becomes evaporated. The acid forms from the combination of sulfur oxide and water in the atmosphere at a height of about 42km. As it condenses and falls, it becomes evaporated back at lower elevations. The surface is therefore protected from the sulfuric acid rain.

The sulfur oxide and water vapor must have been derived from volcanic activities in geologic times past.

(a) [tex]-1.48\cdot 10^{-5}N[/tex]

The electrostatic force exerted between the two sphere is given by:

[tex]F=k\frac{q_1 q_2}{r^2}[/tex]

where

k is the Coulomb's constant

q1, q2 are the charges on the two spheres

r is the separation between the centres of the two spheres

In this problem,

[tex]q_1 = 12\cdot 10^{-9} C\\q_2 = -23\cdot 10^{-9} C\\r = 0.41 m[/tex]

Substituting these values into the equation, we find the force

[tex]F=(9\cdot 10^9 Nm^2 C^{-2} )\frac{(12\cdot 10^{-9}C)(-23\cdot 10^{-9} C)}{(0.41 m)^2}=-1.48\cdot 10^{-5}N[/tex]

And the negative sign means the force is attractive, since the two spheres have charges of opposite sign.

(b) [tex]+1.62\cdot 10^{-6}N[/tex]

The total net charge over the two sphere is:

[tex]Q=q_1 +q_2 = 12\cdot 10^{-9}C+(-23\cdot 10^{-9}C)=-11\cdot 10^{-9} C[/tex]

When the two spheres are connected, the charge distribute equally over the two spheres (since they are identical, they have same capacitance), so each sphere will have a charge of

[tex]q=\frac{Q}{2}=\frac{-11\cdot 10^{-9}C}{2}=-5.5\cdot 10^{-9}C[/tex]

So the electrostatic force between the two spheres will now be

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

And substituting numbers, we find

[tex]F=(9\cdot 10^9 Nm^2 C^{-2} )\frac{(-5.5\cdot 10^{-9} C)^2}{(0.41 m)^2}=+1.62\cdot 10^{-6}N[/tex]

and the positive sign means the force is repulsive, since the two spheres have same sign charges.

The final charge on each sphere after contact will be −4 nC, which reflects the even distribution of the combined charges initially present on both spheres.

When two charged metal conducting spheres are brought into contact, their charges redistribute evenly between them because they are identical. This is because the total charge is conserved, and it will be shared equally when the two spheres touch.

If sphere A has a charge of −5 nC (nanoCoulombs) and sphere B has a charge of −3 nC, after they touch, they will both have the same charge. We calculate the final charge on each by adding the charges together and then dividing by two, which gives us (−5 nC + −3 nC)/2 = −4 nC on each sphere. The −4 nC corresponds to a specific number of electrons, where the charge of one electron is ≎1.6×10−19 C.

The rocket's altitude [tex]y[/tex] at time [tex]t[/tex] is

[tex]y(t)=\left(800\dfrac{\rm km}{\rm h}\right)t[/tex]

so that after [tex]t=3\,\mathrm{min}[/tex], it will have traveled

[tex]y=\left(800\dfrac{\rm km}{\rm h}\right)(3\,\mathrm{min})=40\,\mathrm{km}[/tex]

The angle of elevation [tex]\theta[/tex] at time [tex]t[/tex] is such that

[tex]\tan\theta=\dfrac{y(t)}{13\,\rm km}[/tex]

At the moment when [tex]y(t)=30\,\mathrm{km}[/tex], this angle is

[tex]\tan\theta=\dfrac{30\,\rm km}{13\,\rm km}\implies\theta\approx66.57^\circ[/tex]

Differentiating both sides of the equation above gives

[tex]\sec^2\theta\dfrac{\mathrm d\theta}{\mathrm dt}=\dfrac1{13\,\rm km}\dfrac{\mathrm dy(t)}{\mathrm dt}[/tex]

and substituting the angle [tex]\theta[/tex] found above, and [tex]\dfrac{\mathrm dy(t)}{\mathrm dt}=800\dfrac{\rm km}{\rm h}[/tex], we get

[tex]\sec^2\theta66.57^\circ\dfrac{\mathrm d\theta}{\mathrm dt}=\dfrac1{13\,\mathrm km}\left(800\dfrac{\rm km}{\rm h}\right)[/tex]

[tex]\implies\boxed{\dfrac{\mathrm d\theta}{\mathrm dt}\approx9.73\dfrac{\rm rad}{\rm h}}[/tex]

Final answer:

Using related rates and the tangent function, the rate at which the angle between the telescope and the ground is increasing can be calculated 3 minutes after the rocket's launch.

Explanation:

To solve the problem of a rocket's angle of elevation changing as it travels vertically, we need to apply related rates in calculus. At the time given (3 minutes after lift-off), we should first convert the rocket's speed into meters per second (800 km/hr is approximately 222.22 m/s). Then, we can use the tangent function (tan(θ) = opposite/adjacent), where opposite is the height of the rocket and the adjacent is the distance from the observer to the launching pad (13 km). The rate of change of the angle can be found by differentiating the tangent function with respect to time and then using the chain rule to substitute for dh/dt (the rate at which the height of the rocket is changing).

After calculating the height of the rocket 3 minutes after launch (which would be 222.22 m/s * 180 s = 39999.6 m), we can find the rate of change of the angle as the rocket ascends by using the formula dθ/dt = (1/(1 + (h/13,000)2)) * (dh/dt)/(13,000), substituting h for 39999.6 and dh/dt for 222.22. The final calculation will give us the rate at which the angle between the telescope and the ground is increasing.

Answer:

Proton, neutron, electron

Explanation:

The atom consists of a nucleus, where almost all the mass is concentrated, and electrons orbiting around the nucleus.

The nucleus consists of two types of particles:

- Proton: it has a mass of [tex]1.6726\cdot 10^{-27} kg[/tex], and a positive electric charge of +e ([tex]1.6\cdot 10^{-19}C[/tex])

- Neutron: it has a mass of [tex]1.6749 \cdot 10^{-27}kg[/tex], and it has no electric charge

The third particle that makes an atom is the electron, that orbit around the nucleus:

- Electron: it has a mass of [tex]9.1094\cdot 10^{-31}kg[/tex], and it has a negative electric charge of -e ([tex]-1.6\cdot 10^{-19}C[/tex])

Answer:

proton neutron electron

Explanation:

Has two unlike poles

2

Take for example the Earth, which has two magnetic poles: one in the north and one in the south.

Answer:

D. 5.2Ω

Explanation:

Resistors in parallel have a net resistance of:

R = (1/R₁ + 1/R₂)⁻¹

The 2.0Ω resistor and the 3.0Ω resistor are in parallel, so the combination has a net resistance of:

R = (1/2.0 + 1/3.0)⁻¹

R = 1.2Ω

Resistors in series of a net resistance of:

R = R₁ + R₂

The 4.0Ω resistor is in series with the 2.0Ω/3.0Ω combination.  So the net resistance of all three is:

R = 1.2Ω + 4.0Ω

R = 5.2Ω

Answer:

its potential energy decreases and its electric potential decreases.

Explanation:

Let's consider a radial field for simplicity. We have:

- The electric potential of the field is given by:

[tex]V=\frac{kQ}{r}[/tex]

where

k is the Coulomb's constant

Q is the charge source of the field

r is the distance from Q

We see that the electric potential decreases as we move away from the source. If we consider a positive charge q moving in the direction of the electric field, this charge q will move away from the charge Q (because the field lines generated by the positive particle Q point away from the particle), so the electric potential will decrease.

- The potential energy of the moving charge is given by

[tex]U=qV[/tex]

where q is the magnitude of the charge. As we said previously, V is decreasing while the charge is moving in the direction of the field, so since U is directly proportional to V, U will decrease as well.

image distance,di=10 cm

object distance,do=20cm

magnification, m=di/do

=10/20

=0.5

since the image is virtual, magnification is negative.

therefore m=-0.5

The dwarf planet Pluton, has the most eccentric orbit (more elliptical and elongated) of all the planets, and as a consequence its orbit is "intersected" by the orbit of Neptune.

However, despite this intersection, there is no collision risk between these two bodies, since the orbit of Pluto is located in an orbital plane different from that of the other planets and therefore different from that of Neptune, its nearest neighbor. In addition, the orbit of Pluton is inclined [tex]17\°[/tex] on the the ecliptic plane (plane where the other planets move around the Sun).

Answer:

Making a Hypothesis

Explanation:

-Research the subject of your question. Review the literature and find out as much as you can about previous information and discoveries surrounding your question.

-Develop an educated guess that answers your initial question. This is your hypothesis. Make a prediction based on your hypothesis and state it as a cause-effect relationship.

(a) Both the girl and the boy have the same nonzero angular displacement.

Explanation:

The angular displacement of an object moving in uniform circular motion, as the boy and the girl on the merry-go-round, is given by

[tex]\theta= \omega t[/tex]

where

[tex]\omega[/tex] is the angular speed

t is the time interval

For a uniform object in uniform circular motion, all the points of the object have same angular speed. This means that the value of [tex]\omega[/tex] is the same for the boy and the girl.

Therefore, if we consider the same time interval t, the boy and the girl will also have same nonzero angular displacement.

(b) The girl has greater linear speed.

Explanation:

The linear (tangential) speed of a point along the merry-go-round is given by

[tex]v=\omega r[/tex]

where

[tex]\omega[/tex] is the angular speed

r is the distance of the point from the centre of the merry-go-round

In this problem, the girl is near the outer edge, while the boy is closer to the centre: since the value of [tex]\omega[/tex] is the same for both, this means that the value of r is larger for the girl, so the girl will also have a greater linear speed.

Both the girl and the boy riding on a merry-go-round have the same nonzero angular displacement, and the girl has greater linear speed.

The angular displacement of a body is the product of the angular velocity of the body and the time taken by it. It can be given as,

[tex]\theta=\omega\times t[/tex]

Here, (ω) is the angular velocity and (t) is the time taken.

The girl and the boy are riding on a merry-go-round that is turning at a constant rate. The girl is near the outer edge, and the boy is closer to the center.

Each point of the circular motion, has the same angular speed and therefor the same angular displacement for the same time.

Hence, for a given elapsed time interval, both the girl and the boy have the same nonzero angular displacement.

A girl and a boy are riding on a merry-go-round that is turning at a constant rate. The girl is near the outer edge, and the boy is closer to the center.

As the linear speed is the product of angular velocity and distance of the body from the center of the rotation.

As the girl is at more distance from the center compare to boy. Hence, the girl has greater linear speed.

Learn mote about the angular displacement here;

https://brainly.com/question/13572778

Motor

A motor is a machine that converts electrical energy into mechanical energy. In motors, electric energy is converted into mechanic energy when a magnetic torque acts on a conductor that carries a current. There are different types of motors like DC and AC motors. The moving part of a motor is called the rotor while the stationary part is called stator

The correct option is a.

An electric motor is the device that converts electrical energy into mechanical energy. It does this by passing current through loops of wire in a magnetic field, which turns a shaft converting electricity into mechanical work.

The device which converts electrical energy into mechanical energy is known as the Electric Motor. Blanketed by a magnetic field, an electric motor is composed of loops of wire. When current is passed through these loops, the magnetic field exerts a rotational force or torque on them, rotating a shaft. This process transforms the electrical energy into mechanical work. Generators, on the other hand, work in the opposite direction, converting mechanical energy into electrical energy by moving a conductor coil in a changing magnetic field. Transformers change the voltage of an electrical supply but do not convert between electrical and mechanical energy. The Battery stores energy through chemical means and can provide electrical energy, but does not convert between mechanical and electrical energy directly.

https://brainly.com/question/30033576

#SPJ3

The complete question is here:

The device which is used for converting electrical energy into mechanical energy is called:

A. Electric motor

B. Dynamo

C. Transformer

D. Battery

The wave speed will be 516 m/sec. The wave speed is  the product of the wavelength and the frequency of the wave.

The distance between two successive troughs or crests is known as the wavelength. The peak of the wave is the highest point, while the trough is the lowest.

The wavelength is also defined as the distance between two locations in a wave that have the same oscillation phase.

The given data in the problem is;

v is the speed = ?

f is the frequency= 215.0 Hz.

λ is the wavelength of the wave= 2.4 m

The relationship between the wave's wavelength, frequency, and speed is given as;

wavelength = speed of wave / frequency

The speed of the wave is found as;

[tex]\rm \lambda= \frac{v}{f} \\\\ \rm v = \lambda \times f \\\\\ \rm v = 2.4 \times 215 \\\\ v= 516 \ m/sec[/tex]

Hence, the wave speed will be 516 m/sec.

To learn more about the wavelength, refer to the link;

brainly.com/question/7143261

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Answer:

6.6 beats per second

Explanation:

For a closed-end pipe, the fundamental frequency is given by

[tex]f_1 = \frac{v}{4 L}[/tex]

where

v is the speed of sound

L is the length of the pipe

Here we have

v = 346 m/s

L = 59.9 cm = 0.599 m

So the fundamental frequency is

[tex]f_1 = \frac{346 m/s}{4\cdot 0.599 m}=144.4 Hz[/tex]

The frequency of the signal generator is

[tex]f_2 = 151 Hz[/tex]

So the beat frequency is given by the absolute value of the difference between the two frequencies:

[tex]f_b = |f_1 -f_2|=|144.4 Hz-151 Hz|=6.6 Hz[/tex]

which means that 6.6 beats per second are heard.

Final answer:

To find the beats per second heard by the organ tuner, calculate the fundamental frequency of the organ pipe and then find the difference between this frequency and 151 Hz, which is the pitch from the electronic signal generator.

Explanation:

To calculate the number of beats per second the organ tuner will hear when comparing the pitch from the organ pipe to the electronic signal generator, we must first determine the fundamental frequency produced by the closed-end organ pipe. Given the length of the organ pipe (59.9 cm or 0.599 m) and the speed of sound (346 m/s), we can use the formula for the fundamental frequency of a closed-end pipe, which is f = v / (4L). Therefore, the calculated frequency is f = 346 m/s / (4 × 0.599 m).

Once we have the frequency from the organ pipe, we can find the difference between this frequency and the frequency from the electronic signal generator (151 Hz) to find the number of beats per second (beats/sec = |f₁ - f₂|). The result will give us the beat frequency the organ tuner hears.

the answer is the second one

Answer:

Wind and water erosion are least likely to affect igneous sills and cooled lava flows

Explanation:

Limestone             basalt and quartzite        are also unlikely to undergo erosion or weathering, as are sandstone and chert. Soil and soft rocks such as clays erode very quickly without protection.