Question

a satellite is moving around the earth in a circle. all forces on the satellite except the force of gravity are negligible. which of the following is true of the acceleration resulting from the gravitational force? a it is constant in magnitude but not in direction. b it causes the speed of the satellite to decrease. c it is zero. d it is constant in magnitude and direction.

Answer 1

The correct answer is d) it is constant in magnitude and direction.

When a satellite moves around the Earth in a circular orbit, the gravitational force acting on the satellite provides the necessary centripetal force to keep it moving in a circle. The centripetal acceleration required to maintain circular motion is given by:

a = v²/r

where v is the velocity of the satellite and r is the radius of the circular orbit. The gravitational force provides the necessary centripetal force, so the acceleration resulting from the gravitational force is given by:

a = F_gravity/m

where F_gravity is the gravitational force and m is the mass of the satellite.

Since the mass of the satellite remains constant, the acceleration resulting from the gravitational force is determined solely by the gravitational force. The gravitational force is always directed towards the center of the Earth, and its magnitude depends only on the mass of the Earth and the distance between the satellite and the center of the Earth. Therefore, the acceleration resulting from the gravitational force is constant in both magnitude and direction.