JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
The time dependence of the position of a particle of mass \(m = 2\) is given by \(\vec r\,(t)\, = \,2t\,\hat i\, - 3{t^2}\hat j\) Its angular momentum with respect to the origin at time \(t = 2\) is
- A \(-48\,\hat k\)
- B \(48\,(\hat i\, + \,\hat j)\)
- C \(36\,\hat k\)
- D \( - \,34\,(\hat k\, - \,\hat i)\)
Answer & Solution
Correct Answer
(A) \(-48\,\hat k\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow v = 2\hat i - 6 + \hat j\) \(At\,t = 2\) \(\overrightarrow v = 2\hat i - 12\hat j\) \(\overrightarrow p = m\overrightarrow v = 4i - 24\hat j\) \(At\,t = 2\) \(\overrightarrow r = 4\hat i - 12\hat j\)…
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