Q24 of 149 Page 195

Calculate the torque on the square plate of the previous problem if it rotates about a diagonal with the same angular acceleration.

The torque on the plate acted by the plate of 120g diagonally is


Given


The mass of the plate is 120g, the edges of the square is 5.0 cm and the angular acceleration is 0.2 rad/sec2


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 applied diagonally is



and



where


F is the force applied on the object; r is the radius of the object turning. Turning angle is given by , I is the moment of Inertia, L is the length at which the force is applied. T is the torque of the rod.


Explanation


The moment of Inertia of the plate is known as



Now putting the values in the respective variables of mass and edge length is



Hence, the torque produced by the plate is calculated as




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