Answer: The centripetal force exerted on a satellite in orbit around a planet is provided by the gravitational pull of the planet. The gravitational force of the planet pulls the satellite towards it, providing the necessary centripetal force for the satellite to continue in its orbit.
Explanation: The force that keeps the satellite in its orbit around the planet is the gravitational force. It is the force of attraction between the planet and the satellite. The gravitational force is responsible for providing the centripetal force to keep the satellite in motion. The gravitational force acts on the satellite in a direction towards the centre of the planet, providing the centripetal force necessary to keep the satellite in orbit. The strength of the gravitational force depends on the mass of the planet and the distance between the planet and the satellite. The larger the mass of the planet, the stronger the gravitational force will be, and the smaller the distance, the stronger the gravitational force will be.