Question

The earth (mass = $ 6 \times {10}^{24} $ kg) revolves around the sun with an angular velocity of $ 2 \times {10}^{-7} rad/s$ in a circular orbit of radius $ 1.5 \times {10}^8 km$. The force exerted by the sun on the earth, in newton, is

• A. $ 36 \times {10}^{21}$
• B. $ 27 \times {10}^{39}$
• C. zero
• D. $ 18 \times {10}^{25}$

Answer 1

The Correct Option is A

Mass $(m)= 6 \times {10}^{24}\, kg; $
Angular velocity $ (\omega) = 2 \times {10}^{-7} rad/s $ and
radius $(r) =1.5 \times {10}^{8} \, km = 1.5 \times {10}^{11} \, m $.
Force exerted on the earth $ = mR {\omega}_2 $
$ = (6 \times {10}^{24}) \times ( 1.5 \times {10}^{11} ) \times (2 \times {10}^{-7})^2$
$= 36 \times {10}^{21 }\, N $.