Physics help from experts.

## QUIZ

### Kepler and Newton

#### Instructions

1. The moon has an orbital period of 27.3 days and a mean distance of 3.80 x 105 km from the center of the Earth. Find the distance (km) an artificial satellite is from the center of Earth if its period is minutes.

2. A planet has two moons. the first is 4 times as far from the center of the planet as the second and has a mass that is times the mass of the second. What is the ratio of the gravitational force on the first planet to the gravitational force on the second?

3. Two spherical balls are placed so their centers are 3.70 m apart. The force between them is x 10-8 N. If the mass of the smaller ball is 74.0 kg, what is the mass of the other ball?

4. How far (in km) from the center of the Earth would a person with a weight of 762 N on Earth have to be to have a weight of N?

5. A 36.0 kg child is sitting on a merry-go-round with a radius of 4.00 m. The time it takes the merry-go-round to make one revolution is s. Find the centripetal acceleration of the child.