# If the average distance between Earth and the Sun were doubled, what changes would occur in the sun's gravitational pull on Earth and Earth's period of revolution?

##### 1 Answer

Jan 4, 2017

#### Answer:

Doubling the distance from the sun reduces gravitational pull and increases the orbital period.

#### Explanation:

Using Newton's model of gravity the force or pull

Where G is the gravitational constant, M is the mass of the Sun, m is the mass of the Earth and r is the distance between Sun and Earth.

So, doubling the distance reduces the force by a factor of 4.

Kepler's third law relates the semi-major axis distance

In the case of Earth in its current position

This would make the orbital period