COMEDK · Physics · 8. Rotational Motion
A particle starts rotating from rest. The instantaneous angular displacement is \(\theta = 3t^3 - t^2\), where \(\theta\) is in radian and t in s; The angular velocity at \(t = 1\) s is
- A \(9\ rads^{-1}\)
- B \(3\ rads^{-1}\)
- C \(7\ rads^{-1}\)
- D \(1\ rads^{-1}\)
Answer & Solution
Correct Answer
(C) \(7\ rads^{-1}\)
Step-by-step Solution
Detailed explanation
The angular displacement is given by \(\theta = 3t^3 - t^2\). The angular velocity \(\omega\) is the rate of change of angular displacement with respect to time, given by \(\omega = \dfrac{d\theta}{dt}\). Differentiating \(\theta\) with respect to \(t\):…
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