Gravitational Fields

Question 1

What type of object will experience an attractive force due to gravity?

Answer 1

Any object with a mass will feel an attractive force due to gravity.

Question 2

What is a gravitational field?

Answer 2

A gravitational field is a region in which an object will experience an attractive force (due to gravity).

Question 3

Draw a diagram showing the gravitational field lines of Earth (when looking from a distance).

Answer 3

Question 4

Draw a diagram showing the gravitational field lines of Earth (at Earth’s surface).

Answer 4

Question 5

1) Give the formula for Newton’s law of gravitation.
2) What does G represent in this formula?
3) What must be true of the masses in this formula?

Answer 5

1) F = G x m₁ x m₂

r²

2) G is the gravitational constant, 6.67x10^-11 Nm²kg^-2
3) The masses must be point masses, or uniform spheres (where all the mass acts as if it’s at the centre, i.e. acts as a point mass).