Question

The torque `(tau)` due to a force gives us the turning effect of the force about a fixed point/axis. It is measured by the product of magnitude of force `(F)` and perpendicular distance `(r )` of the line of action of force form the axis of rotation.
`overset rarr(tau) = overset rarr(r ) xx overset rarr(F) = rF sin theta hatn`
where `thete` is smaller angle between `overset rarr(r )` and `hatn` is unit vector along `overset rarr(tau)`.
Read the above passage and answer the following questions :
(i) What is the significance of torque ?
(ii) How do you determine the direction of torque ?
(ii) What is the implication of this concept in day to day life ?

Answer 1

(i) Torque plays the same role in rotational motion as force plays in linear motion.
(ii) The direction of torque, `overset rarr(tau)` is given by right handed screw rule. `overset rarr(tau) _|_ overset rarr(r ) and overset rarr(tau) _|_overset rarr(F)`.
(iii) From `oversetrarr(tau) = overset rarr(r ) xx overset rarr(F) = rF sin theta`, we find that when `theta = 0^(@) = zero`. In day to day life, it implies that when you align yourself along the force (i.e., your boss), the turning effect on you becomes zero, ity, say God, i.e., when you merge your wishes with the wishes of God, you are stable.