What is the coefficient of friction

Question

You move a 45 kg bookcase by pushing it with a force of 65 N. If it accelerates at a rate of 0.15 m/s2, what is the coefficient of friction between the bookcase and the floor

Answer 1

Use Newton's 2nd law.

 

F_net = ma

 

a = 0.15 m/s²

 

F₁ = 65 N

 

f = magnitude of force of friction = μmg

 

m = 45 kg

 

F_net = F₁ - f

 

ma = F₁ - μmg

 

μ = (F₁ - ma) / (mg)

 

Plug in values of F₁, m, and a.  You should be able to finish from here.