4)
When you use a slingshot to fire a rock you stretch the rubber band storing potential
energy. If you stretched the rubber band so that it had 100-J of potential energy,
a)
with how much kinetic energy will the rock leave the slingshot?
with how much kinetic energy will the rock leave the slingshot if it loses 10-J to
heat & sound?
5)
A pendulum has 15-J of potential energy at the top of its swing.
a)
What is its kinetic energy at the bottom of its swing?
b)
At another time the pendulum has 8-J of potential energy. What is its kinetic
energy?
c)
For the pendulum in “b”, what will its kinetic energy be if it loses 2-J to heat?
6
A 1-kg ball is 10-m above a table when it is dropped. It bounces to a height of 7-m.
a)
How much energy is transferred to heat & sound during the bounce?
b)
Explain why this ball cannot bounce to a height of 12-m if it is dropped.
What could you do to make the ball bounce to a height of 12-m?