What term describes the resistance to motion between two moving objects, such as a ball on grass moving slower than on asphalt?

What term describes the resistance to motion between two moving objects, such as a ball on grass moving slower than on asphalt?

• A. Friction
• B. Gravity
• C. Inertia
• D. Drag

Answer: (A)

Friction is the resistance to motion that occurs where two surfaces meet. It acts opposite to the direction of the ball’s motion, converting some of its energy into heat and slowing it down. The rougher grass has a higher friction coefficient, so the ball experiences more resistance and slows more quickly. The smoother asphalt presents less resistance, so the ball keeps moving faster and farther. Gravity, inertia, and drag describe other forces or tendencies (weight, an object’s desire to keep moving, and air resistance, respectively) and don’t describe the interaction between the ball and the ground in the same way as friction does.

Friction is the resistance to motion that occurs where two surfaces meet. It acts opposite to the direction of the ball’s motion, converting some of its energy into heat and slowing it down. The rougher grass has a higher friction coefficient, so the ball experiences more resistance and slows more quickly. The smoother asphalt presents less resistance, so the ball keeps moving faster and farther. Gravity, inertia, and drag describe other forces or tendencies (weight, an object’s desire to keep moving, and air resistance, respectively) and don’t describe the interaction between the ball and the ground in the same way as friction does.