Question

The change in the value of acceleration of earth towards sun, when the moon comes from the position of solar eclipse to the position on the other side of earth in line with sun is :

(mass of the moon $=7.36\times {10}^{22}kg,$ radius of the moon's orbit $=3.8\times {10}^{8}m$)

• A. $6.8\times {10}^{-5}m/s^2$
• B. $6.73\times {10}^{-3}m/s^2$
• C. $6.73\times {10}^{-2}m/s^2$
• D. $673\times {10}^{-3}m/s^2$

Answer 1

The correct option is A $6.8\times {10}^{-5}m/s^2$

solution:

The acceleration during solar eclipse $a_i=a_s+a_m$

similarly when the moon on other side, $a_f=a_s-a_m$

So, change in acceleration $=a_i-a_f=(a_s+a_m)-(a_s-a_m)=2a_m$

But, $2a_m=\frac{2GM}{R^2}=$ $\frac{2\times 6.67\times {10}^{-11}\times 7.36\times {10}^{22}}{(3.28\times {10}^8)2}=6.80\times {10}^{-5}m/s^2$