As a pendulum swings from its highest to its lowest position along an arc, what happens to its kinetic energy and potential energy?

a. both the potential energy and kinetic energy decrease.
b. the potential energy decreases while the kinetic energy increases.
c. the kinetic energy decreases while the potential energy increases.
d. both the potential energy and kinetic energy increase. the bar chart below shows the distribution of the potential, kinetic, and tota

B. The potential energy decreases while the kinetic energy increases.

Explanation:

Potential Energy (PE) = mgh  

where m -mass of object

g- acceleration due to gravity,

But mg is constant, hence the only variable that is changing is the height, and it is directly proportional to the potential energy. This means at the maximum height we have the greatest potential energy. This means that at its highest point, the pendulum possesses maximum potential energy hence as it moves to the lowest point potential energy decreases.

Kinetic energy is given by

Where m is is the mass of the object and v its velocity.

The equation shows that Kinetic energy is directly proportional to the square of velocity. This means kinetic energy is greatest when we have maximum velocity. At its lowest point the pendulum moves with maximum velocity therefore from the highest point to the lowest point velocity is increasing which means kinetic energy is also increasing.

grav potential energy