Question

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

Answer 1

Correct Answer: 125

The correct answer is 125
$a={\omega }^{2}R={\left(\frac{28\times 2\pi }{60}\right)}^2\times 1.8$
$={\left(\frac{56}{60}\times \frac{22}{7}\right)}^2\times 1.8$
$=\frac{(44{)}^2}{225}\times 1.8$
$=\frac{1936\times 1.8}{225}$
\(=\frac{1936}{125}\)
$x=125$