According to the material, why do many solar system bodies orbit the Sun?

• A. Because of centrifugal force
• B. Because of gravitational pull from the Sun
• C. Because of magnetic attraction
• D. Because of solar winds

Answer: (A)

Gravity from the Sun is what keeps solar system bodies in orbit. The Sun’s gravity pulls inward on a planet, and if that body already has sideways, or tangential, motion, gravity continually curves its path rather than letting it fall straight in or fly off. The result is an orbit: a path shaped by the balance between forward velocity and the inward pull. In a circular orbit, the inward pull provides the exact centripetal force needed to keep turning a constant distance around the Sun, which ties the orbital speed to the distance from the Sun. What you’d observe in a rotating frame is a centrifugal feeling, but in the real inertial frame the motion is explained by gravity acting as the central force keeping the object in orbit.