Question

A particle of mass m is attached to M via a massless string passing through a hole O in the horizontal table as shown, Mass M is kept stationary whereas mass m is rotating in a circle of radius r with angular speed $\omega$.

• A. $Mg=mr{\omega }^2$
• B. $Mg>mr{\omega }^2$
• C. $Mg<mr{\omega }^2$
• D. $Mg\ge mr{\omega }^2$

Answer 1

The correct option is A

$Mg=mr{\omega }^2$

Tension provide the necessary centripetal force

$T=m{\omega }^{2}r=Mg$

$m{\omega }^{2}r=Mg$