JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
The position vector of \(1\,kg\) object is \(\overrightarrow{ r }=(3 \hat{ i }-\hat{ j })\,m\) and its velocity \(\overrightarrow{ v }=(3 \hat{ j }+ k )\,ms ^{-1}\). The magnitude of its angular momentum is \(\sqrt{ x } Nm\) where \(x\) is
- A \(89\)
- B \(91\)
- C \(90\)
- D \(95\)
Answer & Solution
Correct Answer
(B) \(91\)
Step-by-step Solution
Detailed explanation
Using \(\overrightarrow{ L }=\overrightarrow{ r } \times \overrightarrow{ p }=\overrightarrow{ r } \times m \overrightarrow{ v }, m =1\,kg\) \(\overrightarrow{ L }=(3 \hat{ i }-\hat{ j }) \times(3 \hat{ j }+\hat{ k })=(9 \hat{ k }-3 \hat{ j }-\hat{ i })\,N - s\)…
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