Question

The Earth exerts a gravitational pull of 2*10^20 N on the Moon;the sun exerts a gravitational pull of 4.3*10^20 N on the Moon.What is the net force on Moon ; when the angular separation between the Earth and the Sun is 90 as seen from the Moon?

Answer 1

Solution:

Net force on Moon:

$F=\sqrt{F^2_1+F^2_2}=\sqrt{(2\sdot{}10^{20})^2+(4.3\cdot{}10^{20})^2}=$

$=\sqrt{(2)^2+(4.3)^2}\cdot10^{20}=\sqrt{22.49}\cdot10^{20}=$

$=4.7\cdot10^{20}$ N.

Answer:

Net force on Moon is $4.7\cdot10^{20}$ N.