A marble is dropped from a toy drone that is 25 m above the ground, and slowly rising with a vertical velocity of 0.8 m/s. How long does it take the marble to reach the ground?

Answers

Answer 1

Answer:

2.18 s

Explanation:

H = - 25 m ( downwards)

U = - 0.8 m/s

g = - 9.8 m/s^2

Let time taken is t.

Use second equation of motion

H = u t + 1/2 g t^2

- 25 = - 0.8 t - 1/2 × 9.8 × t^2

4.9 t^2 + 0.8 t - 25 = 0

By solving we get

t = 2.18 s


Related Questions

In the sport of parasailing, a person is attached to a rope being pulled by a boat while hanging from a parachute-like sail. A rider is towed at a constant speed by a rope that is at an angle of 15 ∘ from horizontal. The tension in the rope is 1900 N. The force of the sail on the rider is 30∘ from horizontal. What is the weight of the rider? Express your answer with the appropriate units.

Answers

Answer:

570 N

Explanation:

Draw a free body diagram on the rider.  There are three forces: tension force 15° below the horizontal, drag force 30° above the horizontal, and weight downwards.

The rider is moving at constant speed, so acceleration is 0.

Sum of the forces in the x direction:

∑F = ma

F cos 30° - T cos 15° = 0

F = T cos 15° / cos 30°

Sum of the forces in the y direction:

∑F = ma

F sin 30° - W - T sin 15° = 0

W = F sin 30° - T sin 15°

Substituting:

W = (T cos 15° / cos 30°) sin 30° - T sin 15°

W = T cos 15° tan 30° - T sin 15°

W = T (cos 15° tan 30° - sin 15°)

Given T = 1900 N:

W = 1900 (cos 15° tan 30° - sin 15°)

W = 570 N

The rider weighs 570 N (which is about the same as 130 lb).

The weight of the rider is 566.89 N.

The given parameters;

Tension in the rope, T = 1900 Nangle of inclination of Tension, = 15⁰The force of sail on the rider, = Fangle of inclination of Force, = 30 ⁰

Let the weight of the rider = W

Apply Newton's second law of motion, to determine the net force in horizontal and vertical direction.

F = ma

Sum of the forces in horizontal direction is calculated as follows;

[tex]\Sigma F_x = 0\\\\Fcos(30) - Tcos(15) = 0\\\\0.866 F - 0.965T = 0\\\\0.866F = 0.965T\\\\F = \frac{0.965T}{0.866} , \ \ T = 1900 \ N\\\\F = \frac{0.965 \times 1900}{0.866} \\\\F = 2,177.21 \ N[/tex]

Sum of the forces in the vertical direction is calculated as follows;

[tex]\Sigma F_y = 0\\\\Fsin(30) - W -Tsin(15) = 0\\\\W = Fsin(30)- Tsin(15)\\\\W = (2117.21 \times 0.5) - (1900\times 0.2588)\\\\W = 566.89 \ N[/tex]

Thus, the weight of the rider is 566.89 N.

Learn more here: https://brainly.com/question/2845632  

The height of the upper falls at Yellowstone Falls is 33 m. When the water reaches the bottom of the falls, its speed is 26 m/s. Neglecting air resistance, what is the speed of the water at the top of the falls?

Answers

Answer:

Speed of water at the top of fall = 5.40 m/s

Explanation:

We have equation of motion

[tex]v^2=u^2+2as[/tex]

Here final velocity, v = 26 m/s

a = acceleration due to gravity

[tex]a=9.8m/s^2 \\ [/tex]

displacement, s = 33 m

Substituting

[tex]26^2=u^2+2\times 9.8 \times 33\\\\u^2=29.2\\\\u=5.40m/s \\ [/tex]

Speed of water at the top of fall = 5.40 m/s

A person is in a room whose walls are maintained at a temperature of 17 °C. The temperature of the person’s skin is 32 °C. The surface area of the person’s skin is 1.4 m2. Determine the netheat transfer rate leaving the person.

Answers

Answer:

sned me short notes of Physics of all branches (post graduation level) thanks  

+923466867221

Explanation:

Two simple pendulums are in two different places. The length of the second pendulum is 0.4 times the length of the first pendulum, and the acceleration of gravity experienced by the second pendulum is 0.9 times the acceleration of gravity experienced by the first pendulum. Determine the comparison of the frequency of the first pendulum to the second pendulum. a) 2/3. b) 3/2 (5 marks) c) 4/9. d) 9/4

Answers

Answer:

[tex]\sqrt{\frac{4}{9}}[/tex]

Explanation:

The frequency of a simple pendulum is given by:

[tex]f=\frac{1}{2\pi}\sqrt{\frac{g}{L}}[/tex]

where

g is the acceleration of gravity

L is the length of the pendulum

Calling [tex]L_1[/tex] the length of the first pendulum and [tex]g_1[/tex] the acceleration of gravity at the location of the first pendulum, the frequency of the first pendulum is

[tex]f_1=\frac{1}{2\pi}\sqrt{\frac{g_1}{L_1}}[/tex]

The length of the second pendulum is 0.4 times the length of the first pendulum, so

[tex]L_2 = 0.4 L_1[/tex]

while the acceleration of gravity experienced by the second pendulum is 0.9 times the acceleration of gravity experienced by the first pendulum, so

[tex]g_2 = 0.9 g_1[/tex]

So the frequency of the second pendulum is

[tex]f_2=\frac{1}{2\pi}\sqrt{\frac{g_2}{L_2}}=\frac{1}{2\pi} \sqrt{\frac{0.9 g_1}{0.4 L_1}}[/tex]

Therefore the ratio between the two frequencies is

[tex]\frac{f_1}{f_2}=\frac{\frac{1}{2\pi}\sqrt{\frac{g_1}{L_1}}}{\frac{1}{2\pi} \sqrt{\frac{0.9 g_1}{0.4 L_1}}}=\sqrt{\frac{0.4}{0.9}}=\sqrt{\frac{4}{9}}[/tex]

Final answer:

The frequency of the first pendulum compared to the second pendulum is in the ratio of 2/3, since the length of the second pendulum is 0.4 times the first and gravity on the second is 0.9 times the first, impacting their respective periods and inversely their frequencies.

Explanation:

The frequency of a simple pendulum is dependent on its length and the acceleration due to gravity it experiences. The formula to find the frequency (f) of a pendulum is given by:

f = 1 / T

Where T is the period of the pendulum, which can be calculated by:

T = 2π√(L/g)

Let's denote L1 and g1 as the length and the acceleration due to gravity for the first pendulum, and L2 and g2 for the second pendulum. Since the length of the second pendulum is 0.4 times that of the first, we have L2 = 0.4L1. And because the acceleration of gravity is 0.9 times for the second pendulum, g2 = 0.9g1.

Using these proportions:

T1 = 2π√(L1/g1)
T2 = 2π√(L2/g2) = 2π√((0.4L1)/(0.9g1))

We can simplify T2 by putting it in terms of T1:

T2 = T1√(0.4/0.9)

Now, since frequency is the inverse of period:

f1 = 1/T1
f2 = 1/T2

So the ratio of their frequencies (f1/f2) will be the inverse of the ratio of their periods (T2/T1):

f1/f2 = T2/T1

Plugging in the ratio:

f1/f2 = √(0.4/0.9) = √(4/9) = 2/3

Therefore, the correct answer is (a) 2/3.

If a planet has the same surface gravity as the earth (that is, the same value of g at the surface), what is its escape speed? (i) The same as the earth's: (ii) less than the earth'sii) greater than the earth's (iv) any of these are possible. I

Answers

Answer:

Explanation:

The escape velocity on a planet is directly proportional to the square root of acceleration due to gravity and the radius of the planet.

According to the question acceleration due to gravity that means g is same but there is no idea about the radius.

So if radius is change then escape velocity at that planet may be more or less depending on the radius.

If the radius is also same then the escape velocity is same.

Starting from rest and height of 7 m, a 3kg object slides down a 30degrees incline, reaching the bottom with a speed of 10m/s . what is the work done by friction? please elaborate.

Answers

Answer:

The work done by the friction is 55.8 J.

Explanation:

Given that,

Height h = 7 m

Mass of the object = 3 kg

Angle = 30°

Speed = 10 m/s

The initial potential energy of the object is converted in to the kinetic energy at the bottom of the incline and  the work done by the friction

[tex]mgh=\dfrac{1}{2}mv^2+W[/tex]

Where, m = mass of the object

v = final velocity

g = acceleration due to gravity

h = height

Put the value in the equation

[tex]3\times9.8\times7=\dfrac{1}{2}\times3\times(10)^2+W[/tex]

[tex]W = (205.8-150)\ J[/tex]

[tex]W=55.8\ J[/tex]

Hence, The work done by the friction is 55.8 J.

How much work must be done by frictional forces in slowing a 1000-kg car from 26.1 m/s to rest? a.3.41 x 10^5 J b.2.73 x 10^5 J c.4.09 x 10^5 J d.4.77 x 10^5 J

Answers

Answer:

Work done by the frictional force is [tex]3.41\times 10^5\ J[/tex]

Explanation:

It is given that,

Mass of the car, m = 1000 kg

Initial velocity of car, u = 26.1 m/s

Finally, it comes to rest, v = 0

We have to find the work done by the frictional forces. Work done is equal to the change in kinetic energy as per work - energy theorem i.e.

[tex]W=k_f-k_i[/tex]

[tex]W=\dfrac{1}{2}m(v^2-u^2)[/tex]

[tex]W=\dfrac{1}{2}\times 1000\ kg(0^2-(26.1\ m/s)^2)[/tex]

W = −340605 J

or

[tex]W=3.41\times 10^5\ J[/tex]

Hence, the correct option is (a).

Final answer:

The work done by frictional forces to slow a 1000 kg car from 26.1 m/s to rest is 3.41 x 10^5 J (a). This value is derived from the car's initial kinetic energy, which is lost due to friction.

Explanation:

The question is asking how much work the frictional forces need to do to bring a 1000 kg car to rest, from an initial speed of 26.1 m/s. In such a scenario, these forces would be working against the car's kinetic energy.

The car's initial kinetic energy can be calculated using the formula 1/2 m v^2 (m = mass, v = speed). So the kinetic energy = 1/2 * 1000 kg * (26.1 m/s)^2 = 3.41 x 10^5 J. Since work done by friction is equal to the change in kinetic energy, and the car is brought to rest, the total work done by frictional forces is 3.41 x 10^5 J. Therefore, the correct answer is (a) 3.41 x 10^5 J.

Learn more about Work Done by Friction here:

https://brainly.com/question/30280752

#SPJ3

g What is the specific heat of silver? The molar heat capacity of silver is 25.35 J/mol⋅∘C. How much energy would it take to raise the temperature of 9.00 g of silver by 18.3 ∘C? Express your answer with the appropriate units.

Answers

Final answer:

The specific heat of silver is 0.235 J/g⋅∘C. It would take 39.1 J of energy to raise the temperature of 9.00 g of silver by 18.3 ∘C.

Explanation:

The specific heat of silver can be calculated using the information given. The molar heat capacity of silver is 25.35 J/mol⋅∘C. To find the specific heat, we need to convert the molar heat capacity to g⋅∘C. The molar mass of silver is 107.87 g/mol. Therefore, the specific heat of silver is 0.235 J/g⋅∘C.

To calculate the amount of energy required to raise the temperature of 9.00 g of silver by 18.3 ∘C, we can use the formula Q = mcΔT, where Q is the energy, m is the mass, c is the specific heat, and ΔT is the change in temperature. Plugging in the values, we get Q = (9.00 g)(0.235 J/g⋅∘C)(18.3 ∘C) = 39.1 J.

Therefore, it would take 39.1 J of energy to raise the temperature of 9.00 g of silver by 18.3 ∘C.

In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 43.4 m/s in a time of 8.59 s. The mass of the car and riders is 3.00 × 10^3 kg. Find the average net force exerted on the car and riders by the magnets.

Answers

Answer:

Average net force, F = 15157.15 N

Explanation:

It is given that,

The mass of the car and riders is, [tex]m=3\times 10^3\ kg[/tex]

Initial speed of the car, u = 0

Final speed of the car, v = 43.4 m/s

Time, t = 8.59 seconds

We need to find the  average net force exerted on the car and riders by the magnets. It can be calculated using second law of motion as :

F = m a

[tex]F=m(\dfrac{v-u}{t})[/tex]

[tex]F=3\times 10^3\ kg\times (\dfrac{43.4\ m/s-0}{8.59\ s})[/tex]

F = 15157.15 N

So, the average net force exerted on the car and riders by the magnets. Hence, this is the required solution.

Final answer:

The average net force comes out to be 15,150 N.

Explanation:

The student has provided information about the Magic Mountain Superman ride, where riders are accelerated by magnets. To find the average net force exerted on the car and riders by the magnets, we can use Newton's second law of motion, which states that the force acting on an object is equal to the mass of the object multiplied by its acceleration (F = m * a).

First, we determine the acceleration using the formula a = (v - u) / t, where 'v' is the final velocity, 'u' is the initial velocity (which is 0 since the car starts from rest), and 't' is the time taken to reach the final velocity.

Using the given data, the acceleration a = (43.4 m/s - 0 m/s) / 8.59 s = 5.05 [tex]m/s^2[/tex]. Now, we can use this acceleration to calculate the force with F = m * a. Substituting the values, we get [tex]F = 3.00 times 103 kg * 5.05 m/s^2 = 1.515 times 104[/tex]N. Hence, the average net force exerted by the magnets on the car and riders is 15,150 N.

The critical angle for diamond (n-2.42) surrounded by air is approximately 24 35 48 66

Answers

Answer:

sin(C) = 1/n = 1/2.42

C = 24.4 deg

The critical angle for the diamond-air interface is 24 degrees.

What is the critical angle for the diamond-air interface?If the ray of light in the diamond medium strikes the separating surface between the diamond and air making an angle more than 24 degrees from the normal to the point of incidence then that ray of light will undergo a total internal reflection and comes back to the diamond medium. This is the reason behind the sparkles of diamonds.Hence, the critical angle for the diamond-air interface is 24 degrees.

To learn more about the critical angle for the diamond-air interface, refer to:https://brainly.com/question/1304781

#SPJ2

A grandfather clock keeps time using a pendulum consisting of a light rod connected to a small heavy mass. With a rod of length L, the period of oscillation is 2.00 s. What should the length of the rod be for the period of the oscillations to be 1.00 s?

Answers

Answer:

The length of the rod should be

[tex]\frac{L}{4} \\ [/tex]

Explanation:

Period of simple pendulum is given by

[tex]T=2\pi\sqrt{\frac{l}{g}} \\ [/tex]

We have

[tex]\frac{T_1^2}{T_2^2}=\frac{l_1}{l_2}\\\\\frac{2^2}{1^2}=\frac{L}{l_2}\\\\l_2=\frac{L}{4} \\ [/tex]

The length of the rod should be

[tex]\frac{L}{4} \\ [/tex]

An overhang hollow shaft carries a 900 mm diameter pulley, whose centre is 250 mm from the centre of the nearest bearing. The weight of the pulley is 600 N and the angle of lap is 180°. The pulley is driven by a motor vertically below it. If permissible tension in the belt is 2650 N and if coefficient of friction between the belt and pulley surface is 0.3, estimate, diameters of shaft, when the internal diameter is 0.6 of the external. Neglect centrifugal tension and assume permissible tensile and shear stresses in the shaft as 84 MPa and 68 MPa respectively.

Answers

Answer:yu

Explanation:

A beam of white light from a flashlight passes through a red piece of plastic. a. What is the color of the light that emerges from the plastic? b. Is the emerging light as intense as, more intense than, or less intense than the white light? Explain. c. The light then passes through a blue piece of plastic. Describe the color and intensity of the light that emerges.

Answers

The light emerging from a red filter is red and less intense than the original white light. When passed through blue plastic, it would be very dim or blocked, as red light cannot pass through a blue filter.

When a beam of white light passes through a red piece of plastic, the color of the light that emerges is red. This color is seen because the red plastic acts as a filter, absorbing other colors and only allowing red light to pass through. The emerging light is less intense than the white light because some of the light energy has been absorbed by the plastic.

If the light that has already passed through a red filter is then passed through a blue piece of plastic, the emerging light would likely be very dim or completely blocked. This is because the red light, lacking blue components, will be mostly absorbed by the blue plastic, which only allows blue light to pass through.

You carry a 7.0-kg bag of groceries 1.2 m above the ground at constant speed across a 2.7m room. How much work do you do on the bag in the process? (A) 157J (B) 0.00J (C) 185J (D) 82J

Answers

Final answer:

In Physics, work is done when a force causes a displacement. Since the bag of groceries is moved horizontally at constant speed and there's no vertical displacement or horizontal force in the direction of motion, the work done on the bag is 0 joules.

Explanation:

The question involves the concept of work in Physics, specifically related to the work-energy principle. In this scenario, the bag of groceries is being carried across the room at a constant speed and constant height. According to the scientific definition of work, work is done when a force causes a displacement in the direction of the force. The formula for work is W = force x displacement. Here, the only forces doing work would be if the bag was lifted or if it was accelerated. Since the bag is being moved at a constant speed and not being lifted any further, there is no work done in the direction of motion, and the vertical height does not change. Therefore, despite the effort you feel you are exerting, the work done on the bag with regard to Physics is 0 joules

Answer choice: (B) 0.00J.

Two balls with masses of 2.10 kg and 6.50 kg travel toward each other at speeds of 13.0 m/s and 4.10 m/s, respectively. If the balls have a head-on inelastic collision and the 2.10-kilogram ball recoils with a speed of 8.20 m/s, how much kinetic energy is lost in the collision?

Answers

Answer:

137 J

Explanation:

Momentum is conserved, so:

(2.10)(13.0) + (6.50)(-4.10) = (2.10)(-8.20) + (6.50) v

v = 2.75 m/s

Energy before collision:

E = 1/2 (2.10) (13.0)² + 1/2 (6.50) (4.10)²

E = 232 J

Energy after collision:

E = 1/2 (2.10) (8.20)² + 1/2 (6.50) (2.75)²

E = 95.2 J

Energy lost in collision:

232 J - 95.2 J = 137 J

Final answer:

A total of 161.488 Joules of kinetic energy is lost in this collision.

Explanation:

The subject question involves a head-on inelastic collision between two balls of different masses traveling towards each other at different speeds and asks for the amount of kinetic energy lost in the collision. To find the kinetic energy lost, we first calculate the initial and final kinetic energies and then take their difference.

Initial kinetic energy (Eki) is the sum of the kinetic energies of the two balls before the collision:

Kinetic energy of the 2.10 kg ball: [tex](1/2) * 2.10 kg * (13.0 m/s)^2[/tex]

Kinetic energy of the 6.50 kg ball: [tex](1/2) * 6.50 kg * (4.1 m/s)^2[/tex]

Final kinetic energy (Ekf) involves only the kinetic energy of the 2.10 kg ball, as the final velocity of the 6.50 kg ball is not given:

Kinetic energy of the 2.10 kg ball: (1/2) * 2.10 kg * [tex](8.20 m/s)^2[/tex]

Kinetic energy lost during the collision is calculated as:

Elost = Eki - Ekf

After calculation:

Initial kinetic energy, Eki = (1/2) * 2.10 kg * [tex](13.0 m/s)^2[/tex] + (1/2) * 6.50 kg * [tex](4.1 m/s)^2[/tex]

Final kinetic energy, Ekf = (1/2) * 2.10 kg * [tex](8.20 m/s)^2[/tex]

Kinetic energy lost, Elost = Eki - Ekf

Plugging the numbers in:

Eki = 0.5 * 2.10 kg * [tex](13.0 m/s)^2[/tex] + 0.5 * 6.50 kg * [tex](4.1 m/s)^2[/tex]
= (0.5 * 2.10 * 169) + (0.5 * 6.50 * 16.81)
= 177.45 J + 54.64 J
= 232.09 J

Ekf = 0.5 * 2.10 kg * [tex](8.20 m/s)^2[/tex]
= (0.5 * 2.10 * 67.24)
= 70.602 J

Therefore, kinetic energy lost, Elost = 232.09 J - 70.602 J = 161.488 J

A total of 161.488 Joules of kinetic energy is lost in this collision.

A 0.144 kg baseball moving 28.0 m/s strikes a stationary 5.25 kg brick resting on small rollers so it moves without significant friction. After hitting the brick, the baseball bounces back, and the brick moves forward at 1.1 m/s (a) For determining baseball's speed after the collision, do you need to use momentum conservation, energy conservation or both? Give reasons for your answer (Marks will only be awarded if reasoning is qiven). (b) What is the baseball's speed after the collision? (c) Find the total mechanical energy before and after the collision. (d) Show that the collision is inelastic. (e) Is the kinetic energy of the system conserved? Give a reason. (f Is the total energy of the system conserved? Give a reason

Answers

(a) Only momentum conservation

In order to find the speed of the ball, momentum conservation is enough. In fact, we have the following equation:

[tex]m u + M U = m v + M V[/tex]

where

m is the mass of the baseball

u is the initial velocity of the baseball

M is the mass of the brick

U is the initial velocity of the brick

v is the final velocity of the baseball

V is the final velocity of the brick

In this problem we already know the value of: m, u, M, U, and V. Therefore, there is only one unknown value, v: so this equation is enough to find its value.

(b) 12.1 m/s

Using the equation of conservation of momentum written in the previous part:

[tex]m u + M U = m v + M V[/tex]

where we have:

m = 0.144 kg

u = +28.0 m/s (forward)

M = 5.25 kg

U = 0

V = +1.1 m/s (forward)

We can solve the equation to find v, the velocity of the ball:

[tex]v=\frac{mu-MV}{m}=\frac{(0.144 kg)(+28.0 m/s)-(5.25 kg)(+1.1 m/s)}{0.144 kg}=-12.1 m/s[/tex]

And the sign indicates that the ball bounces backward, so the speed is 12.1 m/s.

(c)  56.4 J, 13.7 J

The total mechanical energy before the collision is just equal to the kinetic energy of the baseball, since the brick is at rest; so:

[tex]E_i = \frac{1}{2}mu^2 = \frac{1}{2}(0.144 kg)(28.0 m/s)^2=56.4 J[/tex]

The total mechanical energy after the collision instead is equal to the sum of the kinetic energies of the ball and the brick after the collision:

[tex]E_f = \frac{1}{2}mv^2 + \frac{1}{2}MV^2 = \frac{1}{2}(0.144 kg)(12.1 m/s)^2 + \frac{1}{2}(5.25 kg)(1.1 m/s)^2=13.7 J[/tex]

(d)

A collision is:

- elastic when the total mechanical energy is conserved before and after the collision

- inelastic when the total mechanical energy is NOT conserved before and after the collision

In this problem we have:

- Energy before the collision: 56.4 J

- Energy after the collision: 13.7 J

Since energy is not conserved, this is an inelastic collision.

(e) No

As shown in part (c) and (d), the kinetic energy of the system is not conserved. This is due to the fact that in inelastic collisions (such as this one), there are some internal/frictional forces that act on the system, and that cause the dissipation of part of the initial energy of the system. This energy is not destroyed (since energy cannot be created or destroyed), but it is simply converted into other forms of energy (mainly heat and sound).

A 1.7cm diameter pipe widens to 4.7cm. Liquid flows through the first segment at a speed of 4.7m/s. What is the speed of the liquid in the second segment?

Answers

Answer:

Speed of the liquid in the second segment = 0.61 m/s

Explanation:

This discharge is constant.

That is

        Q₁ = Q₂

       A₁v₁ = A₂v₂

       [tex]\frac{\pi d_1^2}{4}\times v_1=\frac{\pi d_2^2}{4}\times v_2\\\\\frac{\pi \times 1.7^2}{4}\times 4.7=\frac{\pi \times 4.7^2}{4}\times v_2\\\\v_2=0.61m/s[/tex]

Speed of the liquid in the second segment = 0.61 m/s

The electric field between square plates of a parallel-plate capacitor has magnitude E. The potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. The magnitude of the electric field between the plates is now equal to a)E b)E/4 c)E/2 d)4E e)2E

Answers

Answer:

the Answer is c: E/2

Explanation:

see attachment

. A hot-air balloon is drifting straight downward with a constant speed of 2.40 m/s. When the balloon is 7.63 m above the ground, the balloonist decides to drop one of the ballast sandbags to the ground below. How much time elapses before the sandbag hits the ground?

Answers

Answer:

1.03 seconds

Explanation:

x = x₀ + v₀ t + ½ at²

0 = 7.63 + (-2.40) t + ½ (-9.8) t²

0 = 7.63 - 2.40 t - 4.9 t²

Solve with quadratic formula:

t = [ -b ± √(b² - 4ac) ] / 2a

t = [ 2.40 ± √(2.40² - 4(-4.9)(7.63)) ] / -9.8

t = -1.52, 1.03

Since t can't be negative here, the sandbag hits the ground after 1.03 seconds.

Final answer:

The sandbag is dropped from the hot air balloon with the balloon's existing speed. Using the second equation of motion and the known values for initial velocity, acceleration due to gravity, and distance, we can solve for the time taken for the sandbag to hit the ground.

Explanation:

In the given question, a hot-Air balloon is drifting straight downward with a constant speed of 2.40 m/s. When the balloon is 7.63 m above the ground, a ballast sandbag is dropped.

Given the bag is dropped from rest relative to the balloon (i.e., the initial velocity (u) of the sandbag is -2.4 m/s, negative because the direction is downward), and the acceleration due to gravity (a) is -9.8 m/s² (negative due to the downward direction), we can use the second equation of motion (s = ut + 0.5at²) where s is the distance covered, which is 7.63 m, to find time (t).

Setting this up, -7.63 = -2.4t + 0.5(-9.8)t². Solving this quadratic equation for time should give us the answer. The result will be the time taken by the sandbag to hit the ground after it is dropped from the hot air balloon.

Learn more about Projectile Motion here:

https://brainly.com/question/29545516

#SPJ2

A person in a kayak starts paddling, and it accelerates from 0 to 0.680 m/s in a distance of 0.428 m. If the combined mass of the person and the kayak is 82.7 kg, what is the magnitude of the net force acting on the kayak?

Answers

To find the magnitude of the net force acting on the kayak, we will use the following kinematic equation derived from Newton's second law of motion:

v2 = u2 + 2as
Where v is the final velocity, u is the initial velocity, a is the acceleration, and s is the distance over which the acceleration occurs.
We know that the kayak starts from rest, so u = 0.
The final velocity v is 0.680 m/s and the distance s is 0.428 m. Rearranging the equation for acceleration a, we get:

a = (v2 - u2) / (2s)

By plugging in the given values, we find that the acceleration a is:
a = (0.6802 - 02) / (2  imes 0.428) = 0.6802 / 0.856 = 0.541 m/s2

Now, using Newton's second law (Force = mass x acceleration), we find the net force F:
F = mass x a
F = 82.7 kg x 0.541 m/s2 = 44.7397 N

The magnitude of the net force acting on the kayak is approximately 44.74 N.

You throw a baseball directly upward at time t = 0 at an initial speed of 12.3 m/s. What is the maximum height the ball reaches above where it leaves your hand? At what times does the ball pass through half the maximum height? Ignore air resistance and take g = 9.80 m/s2.

Answers

Explanation:

At the maximum height, the ball's velocity is 0.

v² = v₀² + 2a(x - x₀)

(0 m/s)² = (12.3 m/s)² + 2(-9.80 m/s²)(x - 0 m)

x = 7.72 m

The ball reaches a maximum height of 7.72 m.

The times where the ball passes through half that height is:

x = x₀ + v₀ t + ½ at²

(7.72 m / 2) = (0 m) + (12.3 m/s) t + ½ (-9.8 m/s²) t²

3.86 = 12.3 t - 4.9 t²

4.9 t² - 12.3 t + 3.86 = 0

Using quadratic formula:

t = [ -b ± √(b² - 4ac) ] / 2a

t = [ 12.3 ± √(12.3² - 4(4.9)(3.86)) ] / 9.8

t = 0.368, 2.14

The ball reaches half the maximum height after 0.368 seconds and after 2.14 seconds.

The maximum height the ball reaches above where it leaves your hand is 7.72 m

The time taken for the ball to pass half of its maximum height moving upwards is 2.14s and 0.37 s when moving downwards.

The given parameters;

initial velocity, u = 12.3 m/s

acceleration due to gravity, g = 9.8 m/s²

The maximum height the ball reaches above where it leaves your hand is calculated as;

[tex]v_f^2 = v_0^2 - 2gh\\\\at \ maximum \ height \ final \ velocity \ v_f = 0\\\\2gh = v_0 ^2\\\\h = \frac{v_0^2}{2g} \\\\h = \frac{(12.3)^2}{2(9.8)} \\\\h = 7.72 \ m[/tex]

The time for the ball to reach half of the maximum height is calculated as;

[tex]half \ of \ the \ maximum \ height = \frac{7.72}{2} = 3.86 \ m[/tex]

[tex]h = v_0t - \frac{1}{2} gt^2\\\\3.86 = 12.3t - 0.5\times 9.8t^2\\\\3.86 = 12.3t - 4.9t^2\\\\4.9t^2- 12.3t + 3.86=0\\\\solve \ the \ quadratic \ equation \ using \ formula \ method;\\\\a = 4.9, \ \ b = -12.3, \ \ c = 3.86\\\\t = \frac{-b \ \ +/- \ \ \sqrt{b^2 - 4ac} }{2a} \\\\t = \frac{-b \ \ +/- \ \ \sqrt{(-12.3)^2 - 4(4.9\times 3.86)} }{2(4.9)} \\\\t = 2.14 \ s \ \ or \ \ 0.37 \ s[/tex]

The time taken for the ball to pass half of its maximum height moving upwards is 2.14s and 0.37 s when moving downwards.

Learn more here: https://brainly.com/question/14580488

At time t=0, a particle is located at the point (3,6,9). It travels in a straight line to the point (5,2,7), has speed 8 at (3,6,9) and constant acceleration 2i−4j−2k. Find an equation for the position vector of the particle.

Answers

The particle has constant acceleration according to

[tex]\vec a(t)=2\,\vec\imath-4\,\vec\jmath-2\,\vec k[/tex]

Its velocity at time [tex]t[/tex] is

[tex]\displaystyle\vec v(t)=\vec v(0)+\int_0^t\vec a(u)\,\mathrm du[/tex]

[tex]\vec v(t)=\vec v(0)+(2\,\vec\imath-4\,\vec\jmath-2\,\vec k)t[/tex]

[tex]\vec v(t)=(v_{0x}+2t)\,\vec\imath+(v_{0y}-4t)\,\vec\jmath+(v_{0z}-2t)\,\vec k[/tex]

Then the particle has position at time [tex]t[/tex] according to

[tex]\displaystyle\vec r(t)=\vec r(0)+\int_0^t\vec v(u)\,\mathrm du[/tex]

[tex]\vec r(t)=(3+v_{0x}t+t^2)\,\vec\imath+(6+v_{0y}t-2t^2)\,\vec\jmath+(9+v_{0z}t-t^2)\,\vec k[/tex]

At at the point (3, 6, 9), i.e. when [tex]t=0[/tex], it has speed 8, so that

[tex]\|\vec v(0)\|=8\iff{v_{0x}}^2+{v_{0y}}^2+{v_{0z}}^2=64[/tex]

We know that at some time [tex]t=T[/tex], the particle is at the point (5, 2, 7), which tells us

[tex]\begin{cases}3+v_{0x}T+T^2=5\\6+v_{0y}T-2T^2=2\\9+v_{0z}T-T^2=7\end{cases}\implies\begin{cases}v_{0x}=\dfrac{2-T^2}T\\\\v_{0y}=\dfrac{2T^2-4}T\\\\v_{0z}=\dfrac{T^2-2}T\end{cases}[/tex]

and in particular we see that

[tex]v_{0y}=-2v_{0x}[/tex]

and

[tex]v_{0z}=-v_{0x}[/tex]

Then

[tex]{v_{0x}}^2+(-2v_{0x})^2+(-v_{0x})^2=6{v_{0x}}^2=64\implies v_{0x}=\pm\dfrac{4\sqrt6}3[/tex]

[tex]\implies v_{0y}=\mp\dfrac{8\sqrt6}3[/tex]

[tex]\implies v_{0z}=\mp\dfrac{4\sqrt6}3[/tex]

That is, there are two possible initial velocities for which the particle can travel between (3, 6, 9) and (5, 2, 7) with the given acceleration vector and given that it starts with a speed of 8. Then there are two possible solutions for its position vector; one of them is

[tex]\vec r(t)=\left(3+\dfrac{4\sqrt6}3t+t^2\right)\,\vec\imath+\left(6-\dfrac{8\sqrt6}3t-2t^2\right)\,\vec\jmath+\left(9-\dfrac{4\sqrt6}3t-t^2\right)\,\vec k[/tex]

Final answer:

To find the equation for the position vector of the particle, use the formula r(t) = r(0) + v(0) * t + (1/2) * a * t^2.

Explanation:

To find the equation for the position vector of the particle, use the following steps:

Write down the initial position vector, r(0), which is (3,6,9).Use the formula for the position vector of a particle with constant acceleration, r(t) = r(0) + v(0) * t + (1/2) * a * t^2, where r(t) is the position vector at time t, v(0) is the initial velocity vector, and a is the constant acceleration vector.Substitute the values into the formula and simplify to get the equation for the position vector.

For the given problem, the equation for the position vector of the particle is: r(t) = (3 + 4t)i + (6 - 4t + 2t^2)j + (9 - 2t + t^2)k.

You are a passenger on a jetliner that is flying at constant velocity. You get up from your seat and walk toward the front of the plane. Because of this action, your forward momentum increases. What happens to the forward momentum of the plane itself?

Answers

Answer:

It feels like it has more weight

It takes 3 s for a rock to hit the ground when it is thrown straight up from a cliff with an initial velocity of 8.63 m/s. How long a time would it take to reach the ground if it is thrown straight down with the same speed?

Answers

Answer:

Explanation:

h = height of the cliff

Consider upward direction as positive and downward direction as negative

Consider the motion of rock thrown straight up :

Y = vertical displacement = - h

v₀ = initial velocity = 8.63 m/s

a = acceleration = - 9.8 m/s²

t = time taken to hit the ground = 3 s

Using the equation

Y = v₀ t + (0.5) a t²

- h = (8.63) (3) + (0.5) (- 9.8) (3)²

h = 18.21 m

Consider the motion of rock thrown down :

Y' = vertical displacement = - 18.21

v'₀ = initial velocity = - 8.63 m/s

a' = acceleration = - 9.8 m/s²

t' = time taken to hit the ground = ?

Using the equation

Y' = v'₀ t' + (0.5) a' t'²

- 18.21 = (- 8.63) t' + (0.5) (- 9.8) t'²

t' = 1.2 s

A bullet is shot horizontally from shoulder height (1.5 m) with an initial speed 200 m/s. (a) How much time elapses before the bullet hits the ground? (b) How far does the bullet travel horizontally?

Answers

Answer: (a)t=0.553s, (b)x=110.656m

Explanation:

This situation is a good example of the projectile motion or parabolic motion, in which the travel of the bullet has two components: x-component and y-component. Being their main equations as follows:

x-component:

[tex]x=V_{o}cos\theta t[/tex]   (1)

Where:

[tex]V_{o}=200m/s[/tex] is the bullet's initial speed

[tex]\theta=0[/tex] because we are told the bullet is shot horizontally

[tex]t[/tex] is the time since the bullet is shot until it hits the ground

y-component:

[tex]y=y_{o}+V_{o}sin\theta t-\frac{gt^{2}}{2}[/tex]   (2)

Where:

[tex]y_{o}=1.5m[/tex]  is the initial height of the bullet

[tex]y=0[/tex]  is the final height of the bullet (when it finally hits the ground)

[tex]g=9.8m/s^{2}[/tex]  is the acceleration due gravity

Part (a):

Now, for the first part of this problem, the time the bullet elapsed traveling, we will use equation (2) with the conditions given above:

[tex]0=1.5m+200m/s.sin(0) t-\frac{9.8m/s^{2}.t^{2}}{2}[/tex]   (3)

[tex]0=1.5m-\frac{9.8m/s^{2}.t^{2}}{2}[/tex]   (4)

Finding [tex]t[/tex]:

[tex]t=\sqrt{\frac{1.5m(2)}{9.8m/s^{2}}}[/tex]   (5)

Then we have the time elapsed before the bullet hits the ground:

[tex]t=0.553s[/tex]   (6)

Part (b):

For the second part of this problem, we are asked to find how far does the bullet traveled horizontally. This means we have to use the equation (1) related to the x-component:

[tex]x=V_{o}cos\theta t[/tex]   (1)

Substituting the knonw values and the value of [tex]t[/tex] found in (6):

[tex]x=200m/s.cos(0)(0.553s)[/tex]   (7)

[tex]x=200m/s(0.553s)[/tex]   (8)

Finally:

[tex]x=110.656m[/tex]  

Final answer:

The bullet will hit the ground after approximately 0.553 seconds, and in that time, it will travel horizontally around 110.6 meters.

Explanation:Calculating Projectile Motion for a Horizontally Fired Bullet

To determine how much time elapses before the bullet hits the ground (1.5 m drop) when fired horizontally at 200 m/s, we use the equation for free fall motion h = (1/2)gt², where h is the height, g is the acceleration due to gravity (approximately 9.8 m/s²), and t is the time in seconds. Solving for time t, we find that the bullet will hit the ground after approximately 0.553 seconds.

For part (b), to find how far the bullet travels horizontally, we simply multiply the time in the air by the bullet's initial horizontal velocity. This gives a horizontal distance of 200 m/s * 0.553 s = 110.6 meters. Therefore, the bullet travels roughly 110.6 meters before hitting the ground.

Learn more about Projectile Motion here:

https://brainly.com/question/29545516

#SPJ3

Which of the following is NOT an example of retaliation?
Getting A Sudden Shift Change
Being Fired
Getting A Promotion
Getting A Bad Performance Review

Answers

Getting a promotion is NOT an example of retaliation.

C. Getting A Promotion

What is retaliation?

the action of harming someone because they have harmed oneself; revenge.

An example of to retaliate is for a person to punch someone who has hit him. (intransitive) To do something harmful or negative to get revenge for some harm; to fight back or respond in kind to damage or affront. Johny insulted Peter to retaliate for Peter's acid remark earlier.

Learn more about retaliation here

https://brainly.com/question/8550165

#SPJ2

A small bulb is rated at 7.5 W when operated at 125 V. Its resistance (in ohms) is : (a) 17 (b) 7.5 (c) 940 (d) 2100 (e) 0.45

Answers

Answer:

Resistance of the bulb is 2100 watts.

Explanation:

Given that,

Power of the bulb, P = 7.5 watts

Voltage, V = 125 volts

We have to find the resistance of the bulb. The power of an electrical appliance is given by the following formula as :

[tex]P=\dfrac{V^2}{R}[/tex]

[tex]R=\dfrac{V^2}{P}[/tex]

[tex]R=\dfrac{(125\ V)^2}{7.5\ W}[/tex]

R = 2083.34 ohms

or

R = 2100 ohms

Hence, the correct option is (d) "2100 ohms"

wo ropes are attached to a 40kg object. The rope with a 50N force points along a direction 49 degrees from the positive x-axis, and the other robe with a 55N force points along a direction 220 degrees. What is the acceleration of the object?

Answers

Answer:

     Acceleration is 0.24 m/s² at 104.44° to positive x-axis.

Explanation:

Refer the figure given.

Let us take component i along positive X axis and component j along positive Y axis.

50 N force can be resolved in to 50 cos 49 i + 50 sin 49 j

        F1 = 32.80 i + 37.74 j

55 N force can be resolved in to 55 cos 220 i + 55 sin 220 j

        F2 = -42.13 i -35.35 j

Total force

       F = F1 + F2 = 32.80 i + 37.74 j -42.13 i -35.35 j = -9.33 i + 2.39 j

We have

      F = ma = 40a =-9.33 i + 2.39 j

Acceleration

      a =-0.233 i + 0.060 j

      [tex]\texttt{Magnitude}=\sqrt{(-0.233)^2+(0.060)^2}=0.24m/s^2[/tex]

      [tex]\texttt{Direction},\theta =tan^{-1}\left ( \frac{0.060}{-0.233} \right )=104.44^0[/tex]

     Acceleration is 0.24 m/s² at 104.44° to positive x-axis.

         

A cylindrical container with 25 ft in diameter is filled to a depth of 22 ft with gasoline (S.G.-0.68). Find the weight of the gasoline and the number of gallons that exist in the tank.

Answers

Answer:

Weight of gasoline = 2039.93 kN

Volume = 80783.80 gallon

Explanation:

Volume = Base area x Depth

[tex]\texttt{Base area = }\frac{\pi d^2}{4}=\frac{\pi \times 25^2}{4}=490.88ft^2[/tex]

Depth = 22 ft

Volume = 490.88 x 22 = 10799.22 ft³ = 10799.22 x 0.0283168 = 305.8 m³

Density of gasoline = 680 kg/m³

Mass of gasoline = 305.8 x 680 = 207943.65 kg

Weight of gasoline = 207943.65 x 9.81 = 2039.93 kN

We have 1 m³ = 264.172 gallon

            305.8 m³ = 305.8 x 264.172 = 80783.80 gallon

A baseball approaches home plate at a speed of 40.0 m/s, moving horizontally just before being hit by a bat. The batter hits a pop-up such that after hitting the bat, the baseball is moving at 57.0 m/s straight up. The ball has a mass of 145 g and is in contact with the bat for 2.10 ms. What is the average vector force the ball exerts on the bat during their interaction? (Let the +x-direction be in the initial direction of motion, and the +y-direction be up.) F

Answers

Answer:

[tex]F = (3.9\times 10^3)\hat j - 2.8 \times 10^3\hat i[/tex]

Explanation:

Initial momentum of the ball is given as

[tex]P_i = mv_i[/tex]

[tex]P_i = 0.145 (40) = 5.8 kg m/s \hat i[/tex]

now final momentum of the ball is given as

[tex]P_f = 0.145(57) = 8.3 kg m/s \hat j[/tex]

now by the formula of force we have

[tex]F = \frac{P_f - P_i}{\Delta t}[/tex]

now we have

[tex]F = \frac{8.3 \hat j - 5.8 \hat i}{2.10 \times 10^{-3}}[/tex]

[tex]F = (3.9\times 10^3)\hat j - 2.8 \times 10^3\hat i[/tex]

The average vector force the ball exerts on the bat during their interaction is

[tex]\rm F = 3.9\times10^3\;\hat{j}-2.8\times10^3\;\hat{i}[/tex]

Given :

Initial Speed = 40 m/sec

Final Speed = 57 m/sec

Mass = 0.145 Kg

Time = 0.0021 sec

Solution :

Initial Momentum is,

[tex]\rm P_i = mv_i[/tex]

[tex]\rm P_i = 0.145\times 40 = 5.8\;Kg .m/sec\;\hat{i}[/tex]

Final momentum is,

[tex]\rm P_f = mv_f = 0.145\times57=8.3\; Kg.m/sec\; \hat{j}[/tex]

Now,

[tex]\rm F=\dfrac{P_f-P_i}{\Delta t}= \dfrac{8.3\hat{j}-5.8\hat{i}}{2.10\times10^-^3}[/tex]

[tex]\rm F = 3.9\times10^3\;\hat{j}-2.8\times10^3\;\hat{i}[/tex]

For more information, refer the link given below

https://brainly.com/question/13492374?referrer=searchResults

Other Questions
12. Which of the following sentences is correct?A. A phrase has a subject and verb, but a clause does not.B. A clause is a group of related words, but a phrase is not.C. A phrase is a group of related words, but a clause is not.D. A clause has a subject and verb, but a phrase does not. Which headline sounds the most credible?OA. "Mars: What the Heck Is Going On Up There?"OB. "Scientists Discover Concrete Evidence of Life on Mars"Oc. "Mars Is Full of Life and Other Stuff, Say Scientists"OD. "Scientists See Some Pretty Crazy Things on Mars" The secretions of the pituitary gland are most directly regulated by the What is the domain of the relation graphed below?A. domain:{-5, -4,-3, -2,0, 1, 2, 3, 4, 5}B. domain:{-3, -2,0, 1,4}C. domain:{-5, -4,-3, 1, 2,5)D. domain:{(-5, 0), (-4, 1), (-3, 4), (1, -2), (2, 4), (5, -3)} The probability that a random variable is greater than or equal to z standard deviations from the mean in a standard normal distribution is p%. What can be said with certainty about the probability that the random variable is less than or equal to z standard deviations from the mean? do you believe that america is a post racial society what is the value of y Which statement is false ? Read these sentences. In a democracy, people rule through elected representatives. It is not a government that is run by the ideas of one leader. This is an example of a formal definition. an informal definition. an extended definition. a dictionary definition. Please help me out brainiest and 30 pointsMatch each of the four lines with a line that is perpendicular to it.Choices to pair with the equations are y=74x+2 y=65x+1y=74x+9y=56x5y=65x5y=47x+2y=47x+9y=56x+1 Social stratification is a system that:ranks society members into categoriesdestroys competition between society membersallows society members to choose their social standingreflects personal choices of society members Acceleration involves a change in speed or what? The following drug reference book is written specifically for medical transcriptionists by a certifiedmedical transcriptionist and lists generic and brand name drugs, as well as how they are used andprescribed M radio station KRTH in Los Angeles broadcasts on an assigned frequency of 101 MHz with a power of 50,000 W. (a) What is the wavelength of the radio waves produced by this station? Answer 1 m (b) Estimate the average intensity of the wave at a distance of 8.70 km from the radio transmitting antenna. Assume for the purpose of this estimate that the antenna radiates equally in all directions, so that the intensity is constant over a hemisphere centered on the antenna. Answer 2 W/m2 (c) Estimate the amplitude of the electric field at this distance. While flying at an altitude of 1.5 km, a plane measures angles or depression to opposite ends of a large crater, shown in the image below. Find the width of the crater Given the following functions f(x) and g(x), solve f over g (5) and select the correct answer below:f(x) = 2x 20g(x) = x 1 5 5 one sixth 30 2(n-1)+4n=2(3n-1)n=0no solutioninfinitely many solutions n= - 4HELP PLEASE!!!!!!! What net external force is exerted on a 1100-kg artillery shell fired from a battleship if the shell is accelerated at 2.40104 m/s2? What is the magnitude of the force exerted on the ship by the artillery shell? FIRST REAL ANSWER GETS BRAINLIEST!!! match the following terms with their definitions:1-Magellan ?-the man for whom the New World was named2-Genoa ?-ruler of the aztecs3-Pizarro ?-discovered the pacific ocean4-Montezuma ?-first to sail around the world5-Cortes ?-conquered the Aztecs of Mexico6-Vespucci ?-conquered the Incas of Peru7-crusaders ?-king of spain8-Balboa ?-attempted to free jerusalem9-Ferdinand ?-hometown of columbus On January 22, 1943, in Spearfish, South Dakota, the temperature rose from 4.00F to 45.0F over the course of two minutes (the current world record for the fastest recorded temperature change). By how much did the temperature change on the Kelvin scale? HINT