Author Question: How was Newton able to calculate the period of revolution of the Moon using his gravitation theory, ... (Read 76 times)

pane00 · **on:** Jul 27, 2018

How was Newton able to calculate the period of revolution of the Moon using his gravitation theory, even though he didn't know the value of G or the masses of the Earth and Moon?

What will be an ideal response?

Question 2

Which of the following has the greatest number of significant figures?

A) 03.1400
B) 314.1
C) 3.142
D) 000.3140
E) 0.003142

14vl19 · **Reply #1 on:** Jul 27, 2018

Answer to Question 1

From GmM/r2 = mv2 / r where m,M are lunar and Earth masses and r distance from Earth to Moon; he got period T = 2 r3/2 / (GM)1/2.
But he knew g=GM/R2 where R is Earth radius, so
T = 2 r3/2 / (gR)21/2 and he knew g, r, and R.

Answer to Question 2

A