Question

Equal torques act on the disc A and B of the previous problem, initially both being at rest. At a later instant, the linear speeds of a point on the rim of A and another point on the rim of B are νA and νB respectively. We have
(a) νA > νB
(b) νA = νB
(c) νA < νB
(d) the relation depends on the actual magnitude of the torques.

Answer 1

Answer:

d the relation depwnds on the actual magnitude of the torques

Answer 2

Option (a)  $v_A$ > $v_B$.

Explanation:

$v_A$ > $v_B$    

τ = Iα  (Magnitude)

We have:  Equal torque    

Torque:

The torque, defined concerning the rotation axis, is equal to the component magnitude of the force vector located in the A vector perpendicular to the centreline, Multiplicated by the shortest distance between axis and force component direction

                $I_A$ $\alpha _A$ = $I_B$ $\alpha _B$

                     $I_A$ < $I_B$

                    $\alpha _A$ > $\alpha _B$  -----> ( i )

Now,

          ω = αt

            Or

          $\frac{v}{r}=\alpha t$

$V_{A}>V_{B}$ ( using ( i ) )

Therefore, option (a) is the correct answer.