What is gravity?

• A. The force which governs the motion of all objects in our solar system.
• B. A property of light that bends around objects
• C. The rate at which planets orbit the Sun
• D. The attraction between masses on Earth only

Answer: (A)

Gravity is the force that attracts objects with mass toward each other. In the solar system, this pull from the Sun keeps planets in ellipses rather than drifting off, and it also binds moons to their planets and governs the paths of comets and asteroids. So, describing gravity as the force that governs the motion of all objects in our solar system best captures its essential role in producing orbital motion. The other statements describe something unrelated to gravity: light bending is about light, not gravity; the rate of orbit is about how fast something goes, not the cause of the motion; and gravity doesn’t stop at Earth—it acts between all masses, everywhere, even though Earth’s gravity is what we feel most directly locally.