lec9 - L ECTURE 9 E NERGY Work Kinetic Energy Potential...

This preview shows pages 1–15. Sign up to view the full content.

L ECTURE 9: E NERGY Work Kinetic Energy Potential Energy Conservation of Energy

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
“Work” is Force times Distance, W = Fd Wilson
Is Work done here? Wilson

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Only the force parallel to the motion counts towards Work Wilson
Kinetic Energy depends on Mass and Speed Brancazio

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Gravitational Potential Energy depends on height since gravity is vertical Wilson.
Elastic Potential Energy Hay

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Elastic Potential Energy Hay
Wilson. 1. When does a weight lifter do work? (a) When lifting the weight (b) When holding the weight over his head (c) Both of these (d) None of these

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2. Which weight lifter did more work? (The barbells have the same mass.) (a) The one on the left (b) The one on the right (c) Both the same 3. Which barbell has more potential energy? (a) The one on the left (b) The one on the right (c) Both the same
4. No work is done by gravity on a bowling ball that rolls along a ﬂat bowling alley because (a) no force acts on the ball. (b) no distance is covered by the ball. (c) the force on the ball is at right angles to the ball’s motion. (d) its kinetic energy remains constant (e) Actually, gravity does do work on the bowling ball. 5. A football that has kinetic energy must be (a) moving (b) falling (c) at an elevated position (d) at rest (e) none of these

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
6. A tennis ball is served at 60 mph. If it is served at 120 mph, its kinetic energy is (a)four times as large (b)twice as large (c)neither of these
Conservation of Energy in Free Fall Hewitt

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Benson
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 22

lec9 - L ECTURE 9 E NERGY Work Kinetic Energy Potential...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online