NEET-XII-Physics
qstns with ansrs year:2022
- #17The angular speed of a fly wheel moving with uniform angular acceleration changes from `` 1200 \,rpm `` to `` 3120\, rpm `` in `` 16 `` seconds. The angular acceleration in `` rad / s ^{2} `` is :
(A) `` 104 \pi ``
(B) `` 2 \pi ``
(C) `` 4 \pi ``
(D) `` 12 \pi ``digAnsr: CAns : `` \omega =\omega_{0}+\alpha t ``
`` \alpha =\frac{\omega-\omega_{0}}{ t } ``
`` =\frac{(3120-1200)}{16 s } rpm ``
`` =\frac{1920}{16} \times \frac{2 \pi}{60} rad / s ^{2} ``
`` =4 \pi rad / s ^{2} ``