Question

For each of the following statements, determine whether it is true or false.

1) Spring A is stiffer than B (kA > kB). Less work must be expended on spring A if both springs are stretched by the same amount.

2) The kinetic energy of an object depends on the direction of the motion involved.

3) The work done to raise a box onto a platform does not depend on how fast it is raised.

4)The friction force is a non-conservative force.

5) The kinetic energy can be negative.

6) The kinetic energy does not depend on the reference frame of the observer.

7)Work can be done in the absence of motion.

8)If the moon revolves around the earth in a perfectly circular orbit, then the earth does do work on the moon.

Answer 1

1) True: Spring A is stiffer than B (kA > kB). Less work must be expended on spring A if both springs are stretched by the same amount.

2) False: The kinetic energy of an object depends on the direction of the motion involved.

3) True: The work done to raise a box onto a platform does not depend on how fast it is raised.

4) True: The friction force is a non-conservative force.

5) True: The kinetic energy can be negative.

6) False: The kinetic energy does not depend on the reference frame of the observer.

7) False: Work can be done in the absence of motion.

8) False: If the moon revolves around the earth in a perfectly circular orbit, then the earth does do work on the moon.