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If force k ˆ 2 – j ˆ 4 i ˆ 3 F + = r acts on a particle having position vector k ˆ 2 j ˆ i ˆ 2 + + then, the torque about the origin will be

1. k ˆ 2 – j ˆ 4 i ˆ 3 +
2. k ˆ 5 j ˆ 10 i ˆ 10 – + +
3. k ˆ 10 – j ˆ 5 i ˆ 10 +
4. k ˆ 5 – j ˆ i ˆ 10 +

Correct answer: k ˆ 5 j ˆ 10 i ˆ 10 – + +

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