Question

A pickup truck with a tailgate down carries two identical sheets of plywood of mass 12 kg stacked in its bed as it accelerates horizontally at a rate of 2.8 m/s^2. The plywood sheets do not slide within the bed or across each other.

a. Neatly draw a force diagram for both sheets of plywood. Label the force vectors appropriately.

b. Circle any force vectors above that have Newton 3rd Law partners present, and connect each pair of circled force vectors with a line to indicate that they form a 3rd law pair.

c. Use your two force diagrams and Newton's laws to find the frictional force that the bed of the truck exerts on the bottom sheet of plywood.