Answer to Question #276400 in Physics for Rakibul

Question

Define the dry friction.

(b) Explain the fluid and solid friction with suitable diagrams. A 500 lb box is sitting

on concrete floor. If the static coefficient of friction is 0.7 and the kinetic

coefficient of friction is 0.6. What is the minimum force required to keep the box

moving once it has started moving?

(c) What is the physical significance of dry friction graph?

Answer 1

Dry friction: friction between dry surfaces.

b) The minimum force required to keep the box moving once it has started moving:

$$F=\mu_km=300\text{ lb}.$$

c) It shows how the coefficient of friction changes with other factors.