Lecture 11

Question 1

What is friction?

Answer 1

A force exerted by a surface as an object moves across it or makes an effort to move across it

Question 2

What can be used to reduce the friction force?

Answer 2

Lubrication

Question 3

What are the 2 types of forces?

Answer 3

Conservative and dissipative(non-conservative)

Question 4

Conservative forces?

Answer 4

• Do no net work over a closed loop
• Kinetic energy is the same at the beginning and the end of the loop
• Does equal work between the two points, regardless of its path

(Gravity, spring force, magnetic force)

Question 5

Dissipative forces?

Answer 5

• Do net work over a closed loop
• Kinetic energy is lost on returning to the same position each time
• Does more work over longer distances

(Friction, viscosity, air resistance)