Which law explains that a soccer ball will not move until it is kicked?

Which law explains that a soccer ball will not move until it is kicked?

• A. Newton's Second Law of Motion
• B. The Law of Gravity
• C. Newton's Third Law of Motion
• D. Newton's First Law of Motion

Answer: (D)

Inertia governs this. Newton’s First Law says an object at rest stays at rest unless a net external force acts on it. The soccer ball is at rest on the ground, with gravity pulling down and the ground pushing up, so these vertical forces balance and there’s no net force to start horizontal motion. When you kick, your foot applies a horizontal force on the ball, creating a net force that accelerates it and makes it move. The other laws describe what happens after a force is present (how acceleration relates to force and mass, or how forces come in action–reaction pairs) and the gravity-driven weight of the ball, but they don’t explain why the ball stays still until a kick.

Inertia governs this. Newton’s First Law says an object at rest stays at rest unless a net external force acts on it. The soccer ball is at rest on the ground, with gravity pulling down and the ground pushing up, so these vertical forces balance and there’s no net force to start horizontal motion. When you kick, your foot applies a horizontal force on the ball, creating a net force that accelerates it and makes it move.

The other laws describe what happens after a force is present (how acceleration relates to force and mass, or how forces come in action–reaction pairs) and the gravity-driven weight of the ball, but they don’t explain why the ball stays still until a kick.