Friction

Monday, 2 April 2018

7:06 PM

Friction force is always against the direction of motion, and therefore does negative work

 

What makes work negative?

The angle of a force relative to the rest of the forces determines the sign of work as per the cosine function.

 

Work defined by conservative forces =

Work defined by non-conservative forces =

 

Recall the work-energy theorem

 

Mechanical energy:

 

 

 

Kinetic Energy  Potential Energy

"If non-conservative forces do no work, "