1) What force keeps an object in circular motion? a) Centrifugal force b) Centripetal force c) Gravitational force d) Friction 2) Kepler's laws of planetary motion describe the motion of planets in: a) Circular orbits b) Elliptical orbits c) Hyperbolic orbits d) Parabolic orbits 3) The weight of an object is the same on every planet in the solar system. a) True b) False

Gravity

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