Introduction to Conservation of Mechanical Energy

What is potential energy?

• Energy stored as a result of the position of the object

• Energy of motion

What is kinetic energy?

• energy of motion

• (1/2)mv

• stored energy

• energy when an object is on the ground

• when an object has zero PE

What important steps were followed here, just as when you learned to calculate work and energy in our class when given a problem?

What happens as the object gets closer to the ground?

• it slows down

• It gains speed or motion

The total distance that the mass falls is 2.0 meters.  Study the data table:  What do you notice about the PE and KE when the mass has fallen halfway down?

What is true about the KE and the PE when the blue and the red lines intersect (cross)?

• The object stops moving

• The KE is equal to the amount of PE

• The total mechanical energy is lowest at this time

• All energy is lost

What is total mechanical energy?

• the potential energy plus the kinetic energy

• the potential energy minus the kinetic energy

Friction causes a loss of mechanical energy. The "lost" energy is changed into thermal energy (heat energy).

• True

• False

When is the Potential Energy at its maximum amount?

• at either end of the pendulum's swing

• at the bottom of the swing

When is the Kinetic Energy at its maximum amount?

• At either end of the pendulum's swing

• At the bottom of the swing