A 500-kg roller coaster car travels with some initial velocity along a track that is 5 m above the ground. The car goes down a small hill and then coasts back up a higher hill. The second hill is 12 m above the ground. What must the initial velocity of the car be for the car to be going 3 m/s at the top of the second hill?

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(20) psi;