PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A 5kg crate lies on a rough horizontal floor. The coefficients of friction between the crate and the floor are μs=0.40 and μk=0.30. A warehouse worker pulls the crate by applying a constant horizontal force of 15N.
Assume g=9.8ms−2. Answer the following.
(i) Compute the normal reaction exerted by the floor on the crate.
(ii) Decide whether the crate remains at rest or starts sliding. Support your decision with quantitative reasoning.
(iii) Find the magnitude of the frictional force acting on the crate in either case.
(iv) Calculate the acceleration of the crate, if any.