Q20 of 149 Page 195

Calculate the total torque acting on the body shown in figure (10-E2) about the point O.


The resultant torque equivalent to 0.54 Nm


Given


The force acting on the heart shaped body as shown in the diagram 10-E2 is given as 10N, 15N, 5N, 20N. The lengths on which the forces applied are 4cm, 4cm, 3cm and 6 cm respectively.


Formula Used


The formula used is that of a torque which tells us the mechanics of force which helps the object to rotate. The formula is



where


F is the force applied on the object; r is the radius of the object turning. Turning angle is given by


Explanation


The torque acting on the point O due to the force of 15N is




The torque acting on the point O due to the force of 10N is




The torque acting on the point O due to the force of 20N is




Due to torque negation between and which leaves them to zero, leaving the resultant torque equivalent to 0.54 Nm.


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