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JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
A particle of mass \(2\, kg\) is moving such that at time \(t\), its position, in meter, is given by \(\overrightarrow r \left( t \right) = 5\hat i - 2{t^2}\hat j\) . The angular momentum of the particle at \(t\, = 2\, s\) about the origin in \(kg\, m^{-2}\, s^{-1}\) is
- A \( - 80\hat k\)
- B \(\left( {10\hat i - 16\hat j} \right)\)
- C \( - 40\hat k\)
- D \( 40\hat k\)
Answer & Solution
Correct Answer
(A) \( - 80\hat k\)
Step-by-step Solution
Detailed explanation
Angular momentum \(L = m\) \((v \times r)\)…
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