After 20 years of astronomical observations in the 1500s with Tycho Brae, Kepler
ID: 2018604 • Letter: A
Question
After 20 years of astronomical observations in the 1500s with Tycho Brae, Kepler concluded that the orbital paths taken by the moon and many other planets had to be elliptical. The moon's distance from the earth varies between 3.56*10^5 km at perigee and 4.07*10^5 km at apogee. This meant that the moon's orbital motion is not exactly uniformly circular in nature, because the moon's distance from the earth can differ by as much as 51000 kmUsing conservation of angular momentum, what is the ratio of the moon's orbital tangential speed around the earth at perigee to that at apogee
Explanation / Answer
m Va Ra = m Vp Rg conservation of angular momentum Vp / Va = Ra / Rp = 4.07 / 3.56 = 1.14