Question

A disc has a mass of 10 kg distribute uniformly and has a radius of 2m. What will be its moment of inertia about an axis passing through its centre and perpendicular to its plane?

• A. 20 $kg-m^2$
• B. 10 $kg-m^2$
• C. 40 $kg-m^2$
• D. None of these

Answer 1

The correct option is A 20 $kg-m^2$

M.I. of disc = $\frac{m{R}^2}{2}$
Given, m = 10 kg
r = 2 m
$\Rightarrow M.I.=\frac{10\times 4}{2}=20kg-m^2$