A body of mass 100 grams is tied to one end of a string and revolved along a circular path in the horizontal plane. The radius of the circle is $50 \mathrm{~cm}$. If the body revolves with a constant angular speed of $20 \mathrm{rad} / \mathrm{s}$, find the 1. period of revolution 2. linear speed 3. centripetal acceleration of the body.
Q 30.2
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Data : $m=100 \mathrm{~g}=0.1 \mathrm{~kg}, \mathrm{r}=50 \mathrm{~cm}=0.5 \mathrm{~m}, \omega=20 \mathrm{rad} / \mathrm{s}$ 1. The period of revolution of the body, $ T=\frac{2 \pi}{\omega}=\frac{2 \times 3.142}{20}=0.3142 \mathrm{~s} $ 2. Linear speed, $v=\omega r=20 \times 0.5=10 \mathrm{~m} / \mathrm{s}$ 3. Centripetal acceleration, $ a_c=w^2 r=(20)^2 \times 0.5=200 \mathrm{~m} / \mathrm{s}^2 $
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