Question

You’re still in a redecorating mood and want to move a 35kg bookcase to a different place in the living room. You exert 58 N on it which makes it move at 0.12 m/s^2. Find the coefficient of kinetic friction between the bookcase and the carpet

Answer 1

Answer: 0.16

Step-by-step explanation:

Newton's second law states that the resultant of the forces exerted on the bookcase is equal to the product between the mass (m) and the acceleration (a):

`F-F_f = ma`

where

F = 58 N is the force applied

Ff is the frictional force

Substituting, we find the frictional force

`F_f = F-ma=58 N-(35 kg)(0.12 m/s^2)=53.8 N`

The frictional force has the form:

`F_f = \mu mg`

where
`\mu` is the coefficient of kinetic friction. Re-arranging the formula, we can find the coefficient:

`\mu=(F_f)/(mg)=(53.8 N)/((35 kg)(9.8 m/s^2))=0.16`