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In the following two exercises, choose t...

In the following two exercises, choose the correct answer from among the given ones, The gravitational intensity at the centre of a hemispherical shell of uniform mass density has the direction indicated by the arrow as shown in figure. (i) a, (ii) b, (iii)c, (iv) 0

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`implies` (a) When semispherical completed it becomes complete spherical shell. Hence gravitational potential is constant at all points in a spherical shell. So intensity of  gravity according to ` I = - (dV)/(dr)` at point C will be zero.

For hemisphere, resultant intensity of gravitation will be toward centre C.
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