If two cars collide, which concept is described?

• A. Friction
• B. Velocity
• C. Attract
• D. Collision

Answer: (D)

A collision describes the moment two bodies come into contact and exert forces on each other, changing their motion. In a car crash, the cars meet and push on one another, which is precisely what a collision entails. Friction is the resistance that occurs when surfaces slide against each other and can affect how the crash unfolds, but it doesn’t name the event itself. Velocity is the speed and direction of motion before or after the event, not the encounter between the cars. Attract would refer to a pulling force (like gravity or magnetism) and isn’t describing the meeting and impact of two moving cars. So the situation is best described as a collision.