Moment of a Force about a Point
Moment of a Force about a Point
This Demonstration shows how to find the torque, or moment of force, exerted by a rope on a boom about the point . The torque is a vector quantity, usually written . You can vary the force and the distance . When distance is expressed in meters (m) and force in newtons (N), the torque or moment has the dimension newton-meters (Nm).
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B
τ
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To find the moment about , multiply the magnitude with the unit vector from to . Next, use the position vector from to the tension . Finally, the torque about is given by the cross product
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A
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τ=rF.