Question

A constant torque of $2000 N - m$, turns a wheel of moment of inertia $300 kg - m ^{2}$ about an axis through the centre. Angular velocity of the wheel after $5 \,s$ will be

• A. $33.3 \,rad / s ^{2}$
• B. $4.44 \,rad / s ^{2}$
• C. $50\, rad / s ^{2}$
• D. None

Answer 1

Answer: (A)

$\tau=I \alpha \Rightarrow $
$ \alpha=\frac{\tau}{I}$
$=\frac{2000}{300}$
$=\frac{20}{3} rad / s ^{2}$
$\omega=\omega_{0}+\alpha t=0+\frac{20}{3} \times 5=\frac{100}{3}$
$=33.3 rad / s ^{2}$