A crate of mass 50 kg is sliding across a frictionless horizontal floor with an…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A crate of mass 50 kg is sliding across a frictionless horizontal floor with an initial speed of 6 m s⁻¹ toward the east. A worker pushes the crate with a steady horizontal force of 100 N directed toward the south for 4 s.
Work out the following.
(i) Find the magnitude of the change in the crate’s linear momentum produced by the push.
(ii) Determine the magnitude and compass direction (bearing) of the crate’s velocity immediately after the 4 s interval.
(iii) Calculate the increase in the crate’s kinetic energy resulting from the push.
(iv) Compute the work done by the worker on the crate and verify that it equals the change in kinetic energy obtained in part (iii).