Question 157: Work, Energy and Power & Circular Motion

Question

A stone tied to $180 \mathrm{~cm}$ long string at its end is making 28 revolutions in horizontal circle in every minute. The magnitude of acceleration of stone is $\frac{1936}{x} ms^{-2}$. The value of $x$ ________. (Take $\pi=\frac{22}{7}$ )

Accepted Answer

Acceleration of stone $a=\frac{v^{2}}{r}=\omega^{2} R$
$$
\begin{aligned}
& a=\left(\frac{28 	imes 2}{60} 	imes \frac{22}{7}ight)^{2} 	imes 1.8 \\
& =\frac{1936}{125}
\end{aligned}
$$
So, $x=125$

Work, Energy and Power & Circular Motion

A stone tied to 180 \mathrm{~cm} long string at its end is making 28 revolutions in horizontal circle in every minute. The magnitude of acceleration of stone is \frac{1936}{x} ms^{-2}. The value of x ________. (Take \pi=\frac{22}{7} )

Choose the correct answer: