Class 11 NEET Physics Gravitation Questions

The acceleration due to gravity at a depth d below surface of earth is
g′=

GM

R2

(1−

d

R

)=g(1−

d

R

)
g′=0 at d=R
i.e., acceleration due to gravity is zero at the centre of earth. Thus, the variation in value of g with r is
For r>R
g′=

g

(1+ h R )2

=

gR2

r2

⇒g′∝

1

r2

Here, R+h=r
For r<R,g′=g(1−

d

R

)=

gr

R

Here, R−d=r⇒g′∝r
Therefore, the variation of g with distance from centre of the earth will be as shown in the figure.