2) A4 kg box slides down a frictionless incline of angle 40 degrees. It starts from rest at time t= 0 at the top of the incline at a height of 25 m above the ground. a) What is the original potential energy of the box relative to the ground? b) Find the distance the box travels in 2 s and its velocity at t = 2 s. c) Find the potential energy and kinetic energy of the box at 2 s. d) Find the kinetic energy and velocity of the box just as it reaches the bottom of the incline.

A child with a weight of 110 N swings on a playground swing attached to 1.90 m long chains. What is the gravitational potential energy (in J) of the child-earth system relative to the child's lowest position at the following times? a) when the chains are horizontal. b) when the chains make an angle of 25.0° with respect to the vertical and c)when the child is at his lowest position

A 2.35-kg object initially at rest has a gravitational potential energy of 74.6 J. Determine the speed of the object when it has moved under the influence of gravity to a location where its gravitational potential energy is 50.0 J. m/s

A. Calculate the work done by the force of gravity when a 5.0kg object is lifted to a height of 30.0m above the ground B. Calculate the velocity with which the object strikes the ground if dropped from that height, using the principle of conservation of energy C. Calculate the kinetic energy and the potential energy of the object at a halfway on the path after it is dropped. To do this part, you need to find the velocity of the object at that position using an equation of motion. What is the total energy of the object at that point? Does this verify the principle of conservation of energy?

An object with a mass of 15kg slides down an incline with a length of 6.0m at an angle of 28 degrees from horizontal.  The coefficient of friction between the object and incline is 0.25  a) How much work does the gravitational force perform on the object? b) How much work does the frictional force perform on the object?  c) What will its speed be as it reaches the bottom of the incline?

A 0.2 kg ball is resting on edge of the top of a 1 m height table. Does the ball have kinetic energy? Explain. Does the ball have potential energy? What is the value of its potential energy? If the ball falls off the table, what happens to its potential energy and kinetic energy during this falling? Which increases/decreases?

An athlete throws a 1.5 kg ball with a horizontal speed of 9 m/s, from a height of 4.8 metres above the ground.  a) Calculate the kinetic energy, gravitational potential energy and total mechanical energy of the ball at its starting position. b) Calculate the maximum speed attained by the ball, just as it reaches the ground's surface.

Conservation of Energy When Work is Done Whiteboard Problems (Page 10):917 \ 1. A 10.0 kg block rests at the top of an incline that is 4.00 m high and 5.00 m long. A) Find the potential energy of the block when it is at the top of the incline. B) What is the speed of the block at the bottom of the incline, if it is frictionless? C) If the incline is not frictionless, and the block experiences a constant 10.0 N force of friction as it moves down the incline, find the speed of the block at the bottom.