## Sliding Box

#### Problem

A 10kg box is placed on the back of a lorry, and as the lorry accelerates uniformly from 0 to 36 kmh^{-1} in 5 seconds, the box begins to slide. The lorry then continues to drive at a constant speed and the box comes to rest.

If the box slides 2 metres in total, and assuming `g`=9.8 ms^{-2}, find μ, the coefficient of friction between the box and the surface.

Problem ID: 155 (Feb 2004) Difficulty: 4 Star