Ellen drops a ball from a cliff. Which statement best describes the ball's energy as it falls from her hand?
a
The ball's potential energy is changed to thermal energy.
b
The ball's kinetic energy decreases while its potential energy increases.
c
The ball's kinetic energy increases but its potential energy remains the same.
d
The ball's potential energy decreases while its kinetic energy increases.
d. The ball's potential energy decreases while its kinetic energy increases.
To answer this question, we need to understand the different types of energy involved. The potential energy of an object is determined by its position relative to a reference point and is based on its mass and height. The kinetic energy of an object is determined by its motion and is based on its mass and velocity.
In this scenario, when Ellen drops the ball from the cliff, the ball initially has potential energy due to its position above the ground. As it falls, this potential energy is converted into kinetic energy, as the ball gains speed during its downward motion.
Therefore, the best statement that describes the ball's energy as it falls from Ellen's hand is option (d): "The ball's potential energy decreases while its kinetic energy increases."