Question

a force of 40.0 N is required to start a 5.0kg box moving across a horizontal concrete floor. a) what is the coefficient of the static friction between the box and the floor? b) if the 40.0 N force continues, the box accelerates at 0.70m/s^2. what is the coefficient of kinetic friction?

Answer 1

\[F=\mu mg\]
\[\mu=.816\]

Answer 2

\[F-\mu mg=ma\]
\[\implies \mu _{k} = .744\]