PHY 1151

Chapter 12, Gravity


| ToC, Chapter 12 | Course Calendar |


D12.1 Calculate the mass of Jupiter, given that its moon Callisto has a mean orbital radius of 1.88 x 106 km and an orbital period of 16 days, 16.54 hours.

D12.2 Starting with the moon's period of 27.3 days, calculate the radius of its orbit.

D12.3 The acceleration of a falling body near Earth’s surface, at a distance R from Earth’s center, is 9.80 m/s2.

(a) Use a suitable proportion to calculate the acceleration toward Earth of a falling body that is 60 R from Earth’s center.
(b) Our moon is in an orbit of radius 60 R, with a period of revolution of 27.26 days. Show, as did Sir Isaac Newton, that the centripetal acceleration of the moon toward Earth agrees with your answer from part (a).

Earth’s radius is R = 6.38 x 103 km.

D12.4 What orbital radius should a weather satellite have if it is to have a period of 6.0 hours?

D12.5 From the data below, calculate the acceleration of free fall on the surface of

a) Jupiter,
b) Saturn, and
c) our Moon.

1 900 x 10^24 kg
71 400 km


561 x 10^24 kg
60 000 km
0.0736 x 10^24 kg
1 740 km

| ToC, Chapter 12 | Course Calendar |


(C) 2005, Doug Davis; all rights reserved