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Three forces, hat i+2hat j-3hat k, 2hat i+3hat j+4hat k, and -hat i-hat j+hat k, act at the point (0,1,2). The resultant moment of these forces about the point A(1,-2,0) is

1. 2hat i-6hat j+10hat k
2. -2hat i+6hat j-10hat k
3. 2hat i+6hat j-10hat k
4. None of these

Correct answer: -2hat i+6hat j-10hat k

Solution

The correct option is derived from calculating the moment generated by each force about point A by using the cross product of the position vector from A to the point of application of the force and the force vector itself. Summing these moments gives the resultant moment, which matches the provided answer.

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