Which of the following best defines gravity?

• A. The frictional force that opposes motion between surfaces
• B. External force that attracts a body toward the earth's center
• C. The energy stored due to height
• D. The weight of an object

Answer: (B)

Gravity is the force of attraction between masses. Near Earth’s surface it acts as an external force pulling objects toward the planet’s center, which is what gives an object its weight and causes it to fall when not supported. This definition captures gravity itself—the universal attraction—rather than the effect of gravity (weight) or related concepts. The frictional force described would oppose motion between surfaces; gravitational potential energy is energy stored by height; weight is the force gravity exerts on a mass, not gravity as a standalone force.