Question

A stone tied to an end of a string 40cm long is whirled in a circle at a constant speed. If the stone makes 28 revolutions in 20 second. Calculate the magnitude of its linear velocity​

Answer 1

$\sf{v=r\omega}\\\\\\\sf{v=r\cdot\dfrac {2\pi n}{t}}\\\\\\\sf{v=40\times\dfrac {2\pi\times28}{20}}\\\\\\\sf{\underline {\underline {v=112\pi\ cm\ s^{-1}}}}\\\\\\\sf{\underline {\underline {v=3.52\ m\ s^{-1}}}}$