What is air resistance?

• A. A force that pushes objects downwards
• B. A force that opposes gravity when an object falls
• C. A force that attracts similar materials
• D. A force that doesn't affect moving objects

Answer: (B)

Air resistance is a type of frictional force that acts against the motion of an object moving through the air. When an object falls, air resistance works to oppose the force of gravity, which pulls the object downward. This resistance arises because air molecules collide with the surface of the falling object, creating a force that slows its acceleration and ultimately influences its terminal velocity.

In the context of falling objects, air resistance increases with the object's speed and surface area. For example, a skydiver may accelerate initially but will eventually reach a constant speed where the downward force of gravity equals the upward force of air resistance, resulting in no further acceleration.

Understanding air resistance is crucial for analyzing motion in a variety of contexts, such as free-fall situations, where its impact becomes particularly significant.