Please answer the following questions about uniform circular motion.? Part (a) A planet orbits a star in a circular orbit at a constant orbital speed, which of the following statements is true?
All of these are correct.
The magnitude of the orbital velocity of the planet is unchanged, thus there is no acceleration and therefore no force action on the planet.
None of these are correct.
The planet experiences a centripetal force pulling towards its star.
The planet experiences no centripetal force.
The planet experiences a centripetal force pushing it away from its star.
Part (b) When a planet is orbiting a star, which force plays the role of the centripetal force?
The force resulting from the planets’ velocity around the star.
The force resulting from the centripetal acceleration.
The gravitational force
Part (c) Which of the following are true statements about uniform circular motion?
An object in uniform circular motion experiences a tangential force.
An object in uniform circular motion experiences a centripetal force, an equal and opposite centrifugal force, and a tangential force.
An object in uniform circular motion experiences a centripetal force and a tangential force.
An object in uniform circular motion experiences a centripetal force.
None of these choices are true.
An object in uniform circular motion experiences no forces.