In which of the following examples is kinetic energy changing into potential energy?
A.
A bicyclist pedals harder.
B.
A rolling ball moves uphill.
C.
A rolling ball moves downhill.
D.
A bicyclist puts on the brakes.

B.  A rolling ball moves uphill.

Explanation:

A rolling ball moving uphill is a typical example of how kinetic energy is changing in to potential energy

Kinetic energy is the energy due to a body in motion.

Potential energy is the energy at rest in a stationary body.

Potential energy is dependent on the mass, height and acceleration due to gravity on a body;

         P. E  = mgh

A ball moving uphill will have its height increasing and this will cause surge in potential energy.

Kinetic energy on the other hand depends on the mass and velocity of a body;

               K.E  = m v²

A ball moving up slope will have the velocity reducing and the kinetic energy reducing.

Therefore, ball rolling uphill will be decreasing in kinetic energy but increasing in potential energy.

your answer would be a. 12.5 kg

the millers tale is the answer.