JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
A force \(\overrightarrow{ F }=4 \hat{ i }+3 \hat{ j }+4 \hat{ k }\) is applied on an intersection point of \(x =2\) plane and \(x\) -axis. The magnitude of torque of this force about a point \((2,3,4)\) is.......... . (Round off to the Nearest Integer)
- A \(16\)
- B \(20\)
- C \(25\)
- D \(12\)
Answer & Solution
Correct Answer
(B) \(20\)
Step-by-step Solution
Detailed explanation
\(\vec{\tau}=\overrightarrow{ r } \times \overrightarrow{ F }\) \(\overrightarrow{ r }=(2 \hat{ i })-(2 \hat{ i }+3 \hat{ j }+4 \hat{ k })=-3 \hat{ j }-4 \hat{ k }\) \( \overrightarrow{ F }=4 \hat{ i }+3 \hat{ j }+4 \hat{ k }\)…
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