ExamBro
ExamBro
MHT CET · Physics · Motion In Two Dimensions

A wheel has a speed of 1200 revolutions per minute and is made to slow down at a rate of \(4 \mathrm{rad} / \mathrm{s}^{2}\). The number of revolutions it makes before coming to rest is

  1. A 143
  2. B 272
  3. C 314
  4. D 722
Verified Solution

Answer & Solution

Correct Answer

(C) 314

Step-by-step Solution

Detailed explanation

\(\omega^{2}=\omega_{0}^{2}-2 a \theta\)
\(0=4 \pi^{2} n^{2}-2 a \theta \)
\(\theta =\frac{4 \pi^{2}\left(\frac{1200}{60}\right)^{2}}{2 \times 4} \)
\(=200 \pi^{2} \mathrm{rad} \)
\(\therefore 2 \pi n =200 \pi^{2} \)
\( n =100 \pi=100 \times 3.14\)
\(=314\) revolution