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 inward toward the sun.
The direction of the sun’s pull relative to the planet’s motion changes.
The direction of the sun’s pull relative to the planet’s motion changes.
The planet’s inertia begins to point backward along its orbit.
The planet’s inertia begins to point backward along its orbit.
The sun’s gravitational pull on the sun decreases.
The correct answer is: The direction of the sun's pull relative to the planet's motion changes.
The correct answer is: The direction of the sun's pull relative to the planet's motion changes.
When a planet moves away from the sun, the direction of the sun's gravitational pull changes. At closer distances, the pull is more towards the center of the planet's orbit, resulting in a stronger gravitational force. As the planet moves further away, the direction of this pull shifts, becoming more perpendicular to the planet's motion. This change in direction of the gravitational pull creates a component of the force that opposes the planet's motion, causing the planet's speed to decrease.
To understand this concept, you can consider the basic principles of how gravitational forces work. The force of gravity between two objects depends on their masses and the distance between them. As an object moves away from a massive body, like the sun, the force of gravity decreases with the square of the distance. Additionally, the gravitational force acts along the line connecting the centers of the two objects. As the planet moves further away from the sun, the angle between the direction of motion and the direction of the sun's pull increases, resulting in a smaller effective force accelerating the planet and causing its speed to decrease.
In summary, as a planet moves away from the sun, the direction of the sun's pull relative to the planet's motion changes, resulting in a decrease in speed due to the opposing component of the gravitational force.