Download presentation

Presentation is loading. Please wait.

Published byRiley Hill Modified over 4 years ago

1
Learning Goal: Students will be able to… - explain how work and energy are related - perform calculations related to kinetic energy and work

2
Energy: Energy: The ability to cause change in self or surroundings. Work: A transfer of energy by physical means. Discuss: What are some forms of energy with which youre already familiar? (And how do those forms match the definition of energy?)

3
Kinetic Energy: Energy possessed by an object due to its motion. KE = ½mv 2 Unit: kg(m/s) 2 = Joules

4
Example Problem: If a 10kg ball possesses 2000J of kinetic energy, how fast must it be moving? Answer: 20m/s

5
The Work-KE Theorem: Discuss: If an object is at rest, then 40J of net work are done on the object, whats the object doing now? So… If a net amount of work is done on an object, energy is transferred to (or from) the object, and the objects kinetic energy will change.

6
The Work-KE Theorem: W net = KE …or… Fdcos = ½mv f 2 - ½mv i 2

7
Example Problem: A 50N net force acts on a 12kg object, increasing its speed from rest. If that force acts through a distance of 5m, what is the final speed of the object? Answer: 6.45m/s

8
Todays HW Answers: 44. The truck required more work. 49.The more massive skater requires a larger stopping distance. 54.125,000J 60.66m 70.a. 86,490J b. 3931N Pg. 306-308 #44, 49, 54, 60, 70

Similar presentations

Presentation is loading. Please wait....

OK

Chapter 8B - Work and Energy

Chapter 8B - Work and Energy

© 2018 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google