Question

Consider the moon orbiting the Earth in a circular path as shown.  Look up the current distance between the Earth and moon as well as the mass of the moon. Model the moon as a particle (ignore the radius of the moon itself.)

a) If the moon orbits the Earth every 27.3 days, what is the angular speed of the moon about the center of the Earth in rad/s?

b) What is the angular momentum of the moon about the Earth?

c) Four and a half billion years ago, the Moon was much closer to the Earth at 2.25e7 m.  What was the angular momentum of the Moon then?

d) Calculate the tangential speeds of the Moon now and four and a half billion years ago?

Answer 1