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Question
Three forces A, B and C are acting on a rigid body which can turn about O in fig.9. If all the three forces are applied simultaneously, in which direction will the body move? Explain.
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Solution
The body will move in the direction of net torque
Net torque = sum of clockwise moments - sum of anticlockwise moments
In the given figure, force 40N is acting clockwise and forces 20N and 60N are acting anticlockwise
Net torque = (40 x 3) - [(20 x 2) + (60 x 1)}
= 120 - 100
= 20 Nm
Hence the body will move in clockwise direction about 'O'
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