1. How does the force of gravity between two bodies change when the distance between them is doubled? 2. How does the brightness of light on a surface change when a point source of light is brought...

1. How does the force of gravity between two bodies change when the distance between them is doubled?

2. How does the brightness of light on a surface change when a point source of light is brought twice as far away?

3. What is the magnitude of gravitational force between two 1-kg bodies that are 1 m apart?