1. Potential and Kinetic Energy…
kinetic energy: is the energy which an object possesses due to its motion
Potential energy: energy stored in a system because of its position.

2. Potential Energy

3. Gravitational Potential Energy
Potential Energy is it has the ability to do work because of position or state.
The energy of an object due to its position above the surface of the Earth.
Ep = W
Potential energy equal to work done!
Ep = Fd

4. Example

5. Change in gravitational potential energy depends only on change in vertical height.

6. Elastic Potential Energy
The energy from a spring being altered from its standard shape.
k: spring constant
x: distance spring is stretched or compressed.

7. Example 2
An apple of mass 0.10 kg is suspended from a vertical spring with spring constant 9.6 N/m. How much elastic potential energy is stored in the spring if the apple stretches the spring 20.4 cm?

8. Example 2
An apple of mass 0.10 kg is suspended from a vertical spring with spring constant 9.6 N/m. How much elastic potential energy is stored in the spring if the apple stretches the spring 20.4 cm?

9. Example 2
An apple of mass 0.10 kg is suspended from a vertical spring with spring constant 9.6 N/m. How much elastic potential energy is stored in the spring if the apple stretches the spring 20.4 cm?

10. Example 2 Follow-Up
How much gravitational potential energy did the apple lose?

11. Example 2 Follow-Up
How much gravitational potential energy did the apple lose?

12. Example 2 Follow-Up
How much gravitational potential energy did the apple lose?

13. Example 2 Follow-Up
How much gravitational potential energy did the apple lose?

14. Pg. 178
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15. Kinetic Energy The energy due to the motion of an object
begin at 43sec
The energy due to the motion of an object
A scalar quantity

17. A 0. 300kg ball is pushed horizontally at a velocity of 20. 0 m/s N
A 0.300kg ball is pushed horizontally at a velocity of 20.0 m/s N. What the Ek of the ball as it moves?

18. The kinetic energy of a moving object is 950 J as it moves 14. 2 m/s
The kinetic energy of a moving object is 950 J as it moves 14.2 m/s. What is its mass?

19. Example 6.5
On a highway, a car with mass of 1200kg and a Ek of 2500 J. What must the velocity of the car be?

20. Practice
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# 4-5
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# 6-7
Pg. 182
#1-3, 5-7,