A man on a skateboard carrying a dictionary is initially at rest. He heaves the dictionary forward with a speed of 0.97 m/s and he recoils backward with a speed of 0.04 m/s. if the dictionary's mass is 3.24kg what is the mass of the man?

it would be kevlar ^^

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.

answer( sicar );