Q. Which one of the following plots represents the variation of gravitational field on a particle with distance $r$ due to a thin spherical shell of radius $R$? ($r$ is measured from the centre of the spherical shell)
AIPMTAIPMT 2012Gravitation
Solution:
Gravitational field due to the thin spherical shell
Inside the shell, i.e. (For $r< R$ )
$F=0$
On the surface of the shell, i.e. (For $r=R$ )
$F=\frac{G M}{R^{2}}$
Outside the shell, i.e. (For $r>R$ )
$F=\frac{G M}{r^{2}}$
The variation of $F$ with distance $r$ from the centre is as shown in the adjacent figure.
