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The coordinates of a particle with respect to origin in a given reference frame is (1, 1, 1) meters. If a force of F = i - j + k acts on the particle, then the magnitude of torque (with respect to origin) in z-direction is .
2
r = i + j + k, F = i - j + k
= r F = vmatrix i & j & k \ 1 & 1 & 1 \ 1 & -1 & 1 vmatrix
= i(1+1) - j(1-1) + k(-1-1) = 2 i - 2 k
z = -2, magnitude = 2 N m
Answer: 2
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