Answer: (D) Both (a) and (c)
The moon travels in a round orbit around the earth. Despite the fact that the orbit is not round, it is elliptical. The centripetal force works on any body moving in a circular motion, and the gravitational force provides the centripetal force in the instance of the motion of the moon around the earth. As a result, option C is the best choice. The moon’s gravitational pull is also responsible for the tides and ocean currents. Tidal force is exerted by the moon, and high and low tides are caused by this force.
Gravity is the force that governs the entire galaxy including planets and stars. In other words, we can say that gravity is the force that acts on all the objects that have mass or energy. Gravity contributes to the weight of the object on the surface of the Earth. Gravity has an infinite range, and the effects of gravity get weaker as the distance between the objects increases. It is denoted by the letter ‘g’.
The universal law of gravitation states that “The force of attraction between any two bodies is directly proportional to the product of their masses and is inversely proportional to the square of the distance between them”