Question

examples of effect of couple in physics

Answer 1

the forces that two hands apply to turn a steering wheel are often (or should be) a couple
Pedals of a Bicycle

Answer 2

examples are:

The forces exerted by one's hand on a screw-driver
The forces exerted by the tip of a screw-driver on the head of a screwDrag forces acting on a spinning propellerForces on an electric dipolein a uniform electric field.
The reaction control systemon a spacecraft.
Force exerted by hands on steering wheel.