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# ## Solution Search

• January 30, 2023
• September 11, 2021
• August 6, 2021
• Iriam
August 4, 2021
• Abhigyan Martin Ninama
September 8, 2017

## . : "Work Power Energy"

### Work Power Energy: Compression in Spring

Q- A particle with mass 10 kg falls from a height of 1.5 m on a vertically mounted spring. If the spring constant is 4000 N/m, calculate the maximum compression in the spring.

Solution:

### Work, Power and Energy

Q- A skier of mass 70 kg is pulled up a slope by a motor driven cable.

(a) How much work is required to pull him 60 m up the 300 slope (assumed friction-less) at a constant speed of 2.0 m/s?

(b) What power must the motor have to perform this task?

Solution:

### Work Power Energy: Conservation of Energy

Q- A particle of mass m=5.00 kg is released from point A and slides on the frictionless track. Determine

(a) the particle's speed at points B and C. and

(b) the net work done by the gravitational force as the particle moves from A to C. Solution:

### Work Done

Q- A block of mass 2.50-kg is pushed 2.20 m along a frictionless horizontal table by a constant 16.0-N force directed 300 below the horizontal. Determine the work done by (a) the applied force, (b) the normal force exerted by the table, (c) the force of gravity, and (d) the net force on the block.

### Momentum and Energy

Q- Two blocks of masses M and 3M are placed on a horizontal, frictionless surface. A light spring is attached to one of them, and the blocks are pushed together with the spring between them. When the blocks released, the block of mass 3M moves to the right with a speed of 2.00m/s

(a) What is the …

### Work Power Energy

Q- A 150 m long rope of mass 250 kg is wrapped on a spool and its 50.0 m is hanging vertically. Now the spool is rotated to pull the rope up slowly. How much work is to be done to pull further 20.0 m of the rope? Neglect any friction force.

Solution:

### Work Power Energy

Q- An object of mass m is traveling on a horizontal surface. There is a coefficient of kinetic friction m between the object and the surface. The object has speed v when it reaches x = 0 and encounters a spring. The object compresses the spring, stops, and then recoils and travels in the opposite di…

### Work Energy Power

Q- An object moves with a velocity of [4m/s, -1m/s, 3m/s] and is acted on by a force of [-5N, 0, +5N]. What is the power of the energy transfer in this interaction?

Solution:

### Linear Momentum

Q- A 25 g bullet is fired into a block of wood sitting on a skateboard. The block and skateboard have combined mass of 22.9 kg. The bullet lodges in the block and the combined system moves away at a velocity of 0.21 m/s. Calculate the initial velocity of the bullet.

Solution:

### WPE - Collision

Q- A ball is launched vertically upwards with an initial velocity of 4 m/s from a height of 8 meters above the ground. the ball rises and then falls to the ground. After hitting the ground once, the ball rises back up to a maximum height of 3 meters. Determine the coefficient of restitution between …

### WPE

(On request - David)

Q- A pile driver of mass 273 KG is allowed to fall through a height of 4 m on a 667 kg steel pile to drive it into the ground. Each impact drives the pile into the ground by 109mm. Assuming that the pile driver remains in contact with the pile after impact, calculate the averag…

### WPE

On request - Mandy

Q- A bungee jumper of mass m is attached to one end of an elastic rope of length L and force constant k. The other end is fixed to a high bridge. The jumper steps off the bridge and falls from rest. If he just reaches the surface of river before going up again find

(a) The heigh…

### WPE

(Requested by Marie)

Q-1 The length of the uncompressed spring is 11.0 cm. The diameter of the wire used to make the spring has been measured using a micrometer screw gauge and has a value of 1.60 mm. The spring has twelve complete turns. When the spring is compressed, the coils are all touching. C…

### WPE

Q- A block of mass 5 kg hangs on a spring. When a second block with an identical mass of 5 kg is  tied to the first, the spring stretches an additional ho = 1 m.

a) What is the value of the spring constant k?

Now the string is burned and the second block falls off.

b) How far above its original …

### Friction

Q1- A block of mass 5.00 kg is pushed up against a wall by a force F that makes a 60.0° angle with the horizontal. The coefficient of static friction between the block and the wall is 0.30. Determine the possible value(s) for the magnitude of F that allow the block to remain stationary.

Q2- A re…

### WPE

Q- A railroad hopper car weighs 50000 kg when empty and contains 50000 kg of coal. As it coasts along the track at 9 m/s the hopper opens and steadily releases all the coal onto a platform below the rails over a period of 6 s.

a) How fast does the car travel after all the coal is dumped?

b) What w…

### WPE

Q- Consider two ideal springs. The spring on the left (constant = 50 N/m) has its left end attached to a fixed wall while its right end is free to move. The spring on the right (constant = 72 N/m) has its right end attached to a fixed wall while its left end is free to move. A block of mass m = 2 kg…

### WPE

Q- A cart of mass M1 = 6 kg is attached to a block of mass M2 = 3 kg by a string that passes over a friction-less pulley. The system is initially at rest and the table is friction-less. After the block has fallen a distance h = 1 m. What is the work Ws done on the cart by the string?

Solution

### WPE

Q1- A girl pulls a box of mass m = 6 kg across a floor with a constant horizontal force F = 35 N. Initially the block is at rest. For the first d1 = 7 m, there is no friction between the box and the floor. For the next d2 = 7 m the coefficient of friction between the box and the floor is m = 0.1.

### WPE Mometntum

Question 1 - A massless spring of spring constant 20 N/m is placed between two carts. Cart 1 has a mass M1 = 5 kg and Cart 2 has a mass M2 = 3.5 kg. The carts are pushed toward one another until the spring is compressed a distance 1.4 m. The carts are then released and the spring pushes them apart. …

20 .