A 0.31-kg particle has a speed of 3.0 m/s at point A and kinetic energy of 8.2 J at point B. (a) What is its kinetic energy at A? J (b) What is its speed at point B? m/s (c) What is the total work done on the particle as it moves from A to B? J

If the force and displacement are in the same direction O a. the work done is independent of the force O b. the work done by the force is zero O c. the work done by the force is maximum O d. work done is independent of the displacement A ball is dropped from the top of a building. As the ball falls down O a. its potential energy is converted to kinetic energy O b, its kinetic energy is converted to potential energy O c. both kinetic energy and potential energy will increase O d. both kinetic energy and potential energy will decrease

Below is the potential energy diagram for a 50 gram particle. If the particle's mechanical energy is 7J: 10 U (1) 9 8 7 6 5 4 3 2 1 0 1 2 3 4 6 7 8 9 10 11 12 x (cm) A. Draw a line corresponding to the total Energy on the diagram. B. Assume the particle is moving in the positive x direction. Where is the particle speeding up? C. Assume the particle is moving in the positive x direction. Where is the particle lowing down? D. Where are any turning points in the particle's motion? E. What is the particle's speed at x=5 cm? F. What is the particle's maximum kinetic energy? Where does that occur? G. Suppose the particle's energy is decreased to 4J while the particle is between positions x = 7 cm and x = 9 cm. What is the particle's new maximum speed? Where does that occur?

A 2kg package is moves up along a 10 m ramp AC inclined at 15' with an initial speed of 5 m/s. Knowing that the coefficient of sliding friction between the package and the incline is 0.2, answer the following questions: 10 m B 15° d 1. What force/s do/does NOT do any work on the package as it moves along the incline? 2. What is the work done by friction on the package as it moves a distance x along the incline? 3. What is the change in the kinetic energy from A to B if at position the package becomes zero? 4. What is the change in the potential energy from A to B if at position B the velocity of the package 5. What is the maximum distance that the package will move up the incline?

A sled and rider with a combined weight of 63 kg are at rest on the top of a hill 19 m high. (a) What is their total energy at the top of the hill? J(b) Assuming there is no friction, what would the total energy be on sliding halfway down the hill? J

1. A slingshot will shoot a 10.0-g pebble 22.0 m straight up. (a) How much potential energy is stored in the slingshot's rubber band? (b) With the same potential energy stored in the rubber band, how high can the slingshot shoot a 25.0-g pebble?

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A 0.500-kg particle has a speed of 1.30 m/s at point A and kinetic energy of 7.00 J at point B. What is its kinetic energy at A? What is its speed at B? What is the net work done on the particle by external forces as it moves from A to B?

A 6.50 kg box slides 4) from the top of a ramp to the bottom at a constant speed, as shown in the diagram. constant v= 1.50 m/s h= 1.85 m 0= 28.2° a) How much work is done on the box by the frictional force? b) How much work is done on the box by gravity? c) How much work is done on the box by the normal force? d) What is the coefficient of kinetic friction between the box and the ramp?

An object of mass m starts at x = A with a speed vi in the +x direction. , where a is a positive 2. For x > A the surface has a coefficient of friction µ(x) constant. Calculate the work done by friction from x = A to an arbitrary point x = B along the box's path of motion. What is the object's kinetic energy at x = B? m Law V1 x = A µ(x) Application