Question

A small particle of mass $0.36$g rests on a horizontal turntable at a distance $25$cm from the axis of the spindle. The turntable is accelerated at a rate of $\alpha$ = 3 rad $s^{-2}$. Find the frictional force that the table exerts on the particle $2$s after the startup.

Answer 1

Small piece of mass $=0.36g$

Distance $=25cm$

Angular acceleration $\alpha =3rad/s^2$

Find the frictional force that the table exerts on the particle$=?$

Now, the time $=2s$ after startup

$f\alpha \times r=3rad/s^2\times 25f=75cm/s^2$

According to Newton's second law

We know that

$F=mf=0.36\times 75cm/s^2=27dyne$