Question

The effect of rotation of the Earth on the value of acceleration due to gravity is

• A. Maximum at both poles
• B. Minimum at both poles
• C. Maximum at equator and minimum at the poles
• D. Minimum at the equator and maximum at the poles

Answer 1

Answer: (C)

As, $g^{′}=g-\omega ^{2} \, Rcos^{2} \lambda $
Now, for poles $\lambda =90^\circ $ and for equation $\lambda =0^\circ $
(i) For $\lambda =90^{ \, }$
$g_{p o l e}^{′}=g-\omega ^{2} \, Rcos^{2} 90^\circ =g$
$g^{′}=g$
There is no effect on $g$ at the poles.
(ii) For $\lambda =0^{ \, }$
$g_{e q u a t o r}=g-\omega ^{2} \, Rcos^{2} 0^\circ $
$= \, g-\omega ^{2} \, R$
The effect of the rotation of Earth on the value of $g$ at the equator is maximum.