Assertion (A): The force of attraction between a hollow spherical shell of uniform density and a point mass situated out side is just as if the entire mass of the shell is concentrated at the centre of the shell. Reason (R): Gravitational forces caused by the various regions of the shell have components along the line joining the point mass to the centre as well as along a direction perpendicular to this line.
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false
Solution:
Assertion (A) is true, it's a direct consequence of Newton's Shell Theorem. Reason (R) is false because, by symmetry, the perpendicular components of gravitational forces from various regions of a uniform spherical shell cancel out, resulting in a net force purely along the line joining the point mass to the center. Therefore, (A) is true but (R) is false.
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