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

The correct option is C maximum at equator and minimum at the poles

As, $g^{\prime }=g-{\omega }^{2}R{\cos }^2\lambda$

Now, for poles $\lambda ={90}^o$ and for equator $\lambda =0^o$

(i) For $\lambda =90$

$g_{pole}^{\prime }=g-{\omega }^{2}R{\cos }^2{90}^o=g$

$g^{\prime }=g$

There is not effect on $g$ at the poles.

(ii) For $\lambda =0$

$g_{equator}=g-{\omega }^{2}R{\cos }^2{0}^o$

$=g-{\omega }^{2}R$

The effect of rotation of the Earth on the value of $g$ at the equator is maximum.