Energy Graph Practice:
1. A ball is dropped from rest from a bridge. As the ball falls through the air, it
encounters a small amount of air resistance. The final state of the ball is the
instant before it strikes the water.
2. A volleyball player spikes the ball at just above net level and drives it over the
net. The initial state is the ball just prior to the spike. The final state of the ball is
the instant before it strikes the ground.
3. 3. A spring gun is used to project a sponge dart into the air at an angle to the
horizontal. The gun is held at a height of 1-meter before the trigger is pulled.
The loaded spring gun is the initial state and the sponge dart at its peak is the
final state.
4. A baseball is caught by a catcher after passing over home plate. The initial state
is the baseball moving at high speed just prior to hitting the catcher's mitt. The
final state is the baseball just after the catcher has applied the force to stop the
ball. Assume that the ball does not change height as the catcher is catching it.
5. In a physics lab, a Hot Wheels car starts at an elevated position, moves down an
incline to the level ground, strikes a box and skids to a stop. Consider three
states for the car: state A is the top of the incline; state B is the bottom of the
incline before striking the box; state C is after the car has been brought to a
stop. Use the diagram at the right and your understanding of the work-energy
theorem to construct bar charts for the motion from A to B and from B to C.