NEET · Physics · STD 11 - 6. system of particles and rotational motion
Find the torque about the orlgin when a force of \(3 \hat{j}\, N\) acts on a particle whose position vector is \(2 \hat{k}\, m \)
- A \(6 \hat{ k }\, Nm\)
- B \(6 \hat{ i }\, Nm\)
- C \(6 j\, Nm\)
- D \(-6 \hat{ i }\, Nm\)
Answer & Solution
Correct Answer
(D) \(-6 \hat{ i }\, Nm\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ F }=3 \hat{j} N , \overrightarrow{ r }=2 \hat{ k }\) \(\vec{\tau}=\overrightarrow{ r } \times \overrightarrow{ F }=2 \hat{ k } \times 3 \hat{j}=6(\hat{ k } \times \hat{ j })\)
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