Certify Teacher Practice Test 2025 - Free Practice Questions and Study Guide

In the context of physics, "work" is defined as the transfer of energy that occurs when a force is applied to an object and the object moves in the direction of that force. For work to be done, there must be both a force exerted on an object and displacement of that object in the direction of the applied force.

When considering the scenario where a runner pushes against a large tree, no movement occurs in the tree despite the force being applied by the runner. The tree remains stationary, and thus there is no displacement. Since work is fundamentally tied to displacement resulting from the application of force, this scenario does not meet the criteria for work being done on an object.

In contrast, the other scenarios involve objects that are either accelerating or being moved as a result of the forces applied. An airplane accelerating through space demonstrates work being done as it utilizes thrust to move forward. A powerlifter pushing a car illustrates work as the car is moved due to the lift's force. A wrecking ball smashing into a wall showcases work through the significant force applied that results in the wall's destruction and movement. Each of these examples includes both force and displacement, which align with the definition of work.