Question
The angular speed of a fly wheel moving with uniform angular acceleration changes from $1200\,rpm$ to $3120\,rpm$ in $16$ seconds. The angular acceleration in $rad/s^{2}$ is :
✓
Answer
$\omega=\omega_{0}+\alpha t$
$\alpha=\frac{\omega-\omega_{0}}{ t }$
$\,\,\,\,=\frac{(3120-1200)}{16 s } rpm$
$\,\,\,\,=\frac{1920}{16} \times \frac{2 \pi}{60} rad / s ^{2}$
$\,\,\,\,=4 \pi rad / s ^{2}$
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