A couple of 105 (Nm) is applied to a disk of mass 10 kg and 50 m radius of gyration. The value of angular acceleration (in rad / s2) will be

We know thatτ=Iα…(i)here τ=105 NmI=mK2…(ii)m = 10 kg and K = radius ofgyration = 50 mSo I=(10)(50)2  (from eq. (ii))So I=2.5×104kgm2Now from eq.  (i) 105=2.5×104(α)So α=4rads−2