Question

In Case 1, a force F is pushing perpendicular on an object a distance L/2 from the rotation axis. In Case 2 the same force is pushing at an angle of 30 degrees a distance L from the axis.1)In which case is the torque due to the force about the rotation axis biggest?
a. Case 1b. Case 2c. Same

Answer 1

Explanation:

Case 1,

A force F is pushing perpendicular on an object a distance L/2 from the rotation axis. Torque is given by :

$\tau_1=Fd\sin \theta\\\\\tau_1=\dfrac{FL}{2}\sin (90)\\\\\tau_1=\dfrac{FL}{2}\ ..........(1)$

Case 2,

The same force is pushing at an angle of 30 degrees a distance L from the axis. New torque is given by :

$\tau_2=Fd\sin \theta\\\\\tau_2=FL\sin (30)\\\\\tau_2=\dfrac{FL}{2}\ ..........(2)$

From equation (1) and (2), it is clear that the force in both cases is same.