Question

A balanced rigid disc mounted on a rigid rotor has four identical point masses, each of 10 grams attached to four points on the 100 mm radius circle shown in the figure.

The rotor is driven by a motor at unifor angular speed of 10 rad/s. If one of the masses gets deteched then the magnitude of the resultant unbalance force on the rotor is N.(round off to 2 decimal places).

Answer 1

$\omega =10rad/s,r=100mm=0.1$ m
If one mass is deteched then


Now, unbalance force,
$F=mr{\omega }^2$
$=\frac{10}{1000}\times 0.1\times (10{)}^2=0.1N$