Question

One goes from the centre of the earth to a distance two third the radius of the earth. The acceleration due to gravity is highest at

• A. the centre of the earth
• B. a distance half the radius of the earth
• C. a distance one-third of the radius of the earth
• D. a distance two-third of the radius of the earth

Answer 1

Answer: (D)

The acceleration due to gravity at a depth $d$ inside the earth is
$g^{\prime }=g\left(1-\frac{d}{R}\right)=g\left(\frac{R-d}{R}\right)=g\frac{r}{R}$
where, $R-d=r=$ distance of a place from the centre of earth, therefore, $g^{\prime }\propto r$