Question 206: Gravitation

Question

A solid sphere of mass 'M' and radius 'a' is
surrounded by a uniform concentric spherical
shell of thickness 2a and mass 2M. The
gravitational field at distance '3a' from the
centre will be :

Accepted Answer

We use GaussÃ¢ÂÂs Law for gravitation
g.4$$\pi $$r
2
= (Mass enclosed) 4$$\pi $$G
$$g = {{3M4\pi G} \over {4\pi {{(3a)}^2}}} = {{GM} \over {3{a^2}}}$$

Answer

$${{GM} \over {3{a^2}}}$$

Answer

$${{2GM} \over {9{a^2}}}$$

Answer

$${{GM} \over {9{a^2}}}$$

Answer

$${{2GM} \over {3{a^2}}}$$

Gravitation

A solid sphere of mass 'M' and radius 'a' is surrounded by a uniform concentric spherical shell of thickness 2a and mass 2M. The gravitational field at distance '3a' from the centre will be :

Choose the correct answer: