2. Work and Kinetic Energy

3. Why are they clapping he did not do work

4. K.E is a scalar Quantity K.E Can not be Negative K.E is measured by Joule (J)

5. Work Work is energy transferred to or from an object by means of force acting on the object Work is said to be positive if transferred to the object and negative if transferred from the object Work is a scalar quantity that has the same units of Energy ( Joule )

6. What is work ? What is the difference between work and doing work ? And what are the units of work ?.

7. I applied the breaks to stop the car what work did friction do on my car ?

8. Answer

11. Can we replace the forces by their resultant ? Then work is defined as:And work K.E theorem becomes

12. =10N =12N What is the work done by mg and N ?

14. Moving Down Moving up If it starts from rest and ends at rest or if it moves with constant velocity then

15. Sample Problem As the box is stationary at the the start and the end of the motion

16. Sample Problem Alternative way