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A rigid body is rotating about an axis. One force F1 acts on the body such that its vector passes through the axis of rotation. Another force F2 acts on it such that it is perpendicular to the axis of rotation and at a point 5cm from the axis. This force F2 is perpendicular to the radius vector at its point of application. Find the net torque on the body. Let F1 = 10N & F2= 5N.

A rigid body is rotating about an axis. One force F1 acts on the body such that its vector passes through the axis of rotation. Another force F2 acts on it such that it is perpendicular to the axis of rotation and at a point 5cm from the axis. This force F2 is perpendicular to the radius vector at its point of application. Find the net torque on the body. Let F1 = 10N & F2= 5N. Correct Answer 0.25Nm

The force F1 passes through the axis of rotation, so it will not produce a torque. The force F2 is perpendicular to axis and radius, so it will provide a torque = r*F2 about the axis of rotation, where ‘r’ is the distance of point of application of force F2 from the axis of rotation. Therefore, torque = r* F2= 0.05 * 5 Nm = 0.25Nm.

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