Question

A string breaks under a tension of $10kg$ $wt.$ If the string is used to revolve a body of mass $1.2kg$ in a horizontal circle of radius $50cm$, what is the maximum speed with which the body can be revolved? When revolving at maximum speed, what is the time period and frequency of revolutions of the body?

Answer 1

(a.) $T_{man}=10\times g=100Nr=50cm=0.5mm=1.2KgasT=\frac{m{v}^2}{r}as100=\frac{1.2\times v^2}{0.5}\Rightarrow v=6.45\frac{m}{s}$

(b.) $T=timeperiod=\frac{2\pi r}{v}=\frac{2\pi \times 0.5}{6.45}=0.48s$

(c.) $f=frequencyofrevolution=\frac{1}{Timeperiod}=\frac{2.08}{s}$