Since, the gravitational intensity is defined as the negative of the gradient of gravitational potential i.e.,\((-\frac {dv}{dr})\) and the value of gravitational potential inside the spherical shell is constant, the value of gravitational intensity is zero.
Consider any point p as shown, inside a sphere then the net gravitational intensity at that point is zero. If the upper half is cut off, the pull in the left and right side cancel each other just like the full sphere base but the pull upwards is missing. Thus the effective force is downwards along E.
