Tag: the turning effect of a force

a couple produces rotational motion of a body . 

While opening a tap with two fingers, a couple should be applied which is defined as a pair of parallel equal forces acting in opposite direction about two different axis.

Two equal and opposite forces are applied about different axis, which is termed as couple, to unwind a screw.

Torque acting about any point O         $\tau _o = rF$                 for $sin\theta = 1$

We know, 

See-saw, Swing and Toy horse are the playground equipment make use of the turning effect of forces.

spanner with longer handle needs less force to generate same torque than with spanner with short handle .

if the base area will be heavy than the centre of gravity will be near to ground and if the base area is curved than the object will come in its balanced position everytime due gravitational torque.

cycling , swimming , badminton and hockey all these sports makes use of turning effect  of forces while play.