Why does the speed of a planet decrease as it moves away from the sun?(1 point)
Responses
The planet’s inertia begins to point inward toward the sun.
The planet’s inertia begins to point backward along its orbit.
The direction of the sun’s pull relative to the planet’s motion changes.
The sun’s gravitational pull on the sun decreases.
The direction of the sun’s pull relative to the planet’s motion changes.
The correct response is: The direction of the sun’s pull relative to the planet’s motion changes.
The correct response is: The direction of the sun’s pull relative to the planet’s motion changes.
When a planet moves away from the sun, the gravitational force between the planet and the sun becomes weaker. This weaker gravitational force means that the centripetal force acting on the planet decreases. As a result, the planet's velocity decreases and its speed reduces. This decrease in speed is due to the change in the direction of the sun's gravitational pull relative to the planet's motion. When the planet is closer to the sun, the gravitational force pulls it inward, which keeps it moving in its orbit at a higher speed. As the planet moves away from the sun, the gravitational force pulls it backward along its orbit, opposing its motion and causing its speed to decrease.