Question

Pls tell me solution

Answer 1

$\bold {\huge {Answer :-}}$

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✭Moment of Inertia✭

Given that,

➛Side = l

➛Mass per unit area = μ

⇨ Total mass M = μl²

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⇨ Now, the moment of inertia is

$\bold{I=\frac{M. R^2}{12}}$

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⇨ By perpendicular axis theorem

$\bold{I=I_x+I_y}$

$\bold{since\:it \:is\:Square }$

$\bold{\:so\:moments \:of\:inertia }$

$\bold{\:along\:both\:plain\:will\:be\:same\:}$

$\bold{Hence,→ I_x=I_y}$

⇨ $\bold{I=2I_x}$

$\bold{\Rightarrow\:I=2\times\:\frac{\mu\:l^2\:\times\:l^2}{12}}$

$\bold{\Rightarrow\:I=\frac{\mu\:l^4}{6}}$

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Hence, the moment of inertia of a square sheet is $\bold{\frac{\mu\:l^4}{6}}$

→option (d)