Dependence of intensity of gravitational field `(E)` of earth with distance `(r)` from centre of earth is correctly represented by

Options

A.
B.
C.
D.

Answer

A

Explanation

For a point inside the earth i.e. r < R
` E = - (GM)/(R^3) r`
where M and R be mass and radius of the earth respectively. At the centre, r=0
` therefore ` E= 0
For a point outside the earth i.e. r > R,
` E = - (GM)/(r^2)` On the surface of the earth i.e. r=R, E= ` - (GM)/(R^2)`
The variation of E with distance r from the centre is as shown in the figure.