A bicyclist is finishing repair of a flat tire when a friend rides by with a constant speed of 4 m/s.
Three seconds later the bicyclist hops on their bike
and accelerates at 2 m/s2 until he catches the friend.
How long does it take the bicyclist to catch the friend
from the moment the bicyclist first hops on their
bike?

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.