Q. 5

# A uniform square plate has a small piece Q of an irregular shape removed and glued to the centre of the plate leaving a hole behind (Fig. 7.3). The moment of inertia about the z-axis is then

A. increased

B. decreased

C. the same

D. changed in unpredicted manner

Answer :

As the piece Q is removed and glued to centre, the moment of inertia decreases about z-axis as the

M.I

As the distance of that piece from z-axis is decreased to zero, hence its M.I will decrease. Hence, correct option is b.

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