Description : Optical fibre works on the principle of (1) refraction (2) scattering (3) interference (4) total internal reflection
Last Answer : (4) total internal reflection Explanation: Since Torque = force x distance, to open a door easily, the handle should be fixed at the greatest distance from the hinges. If we pull with same force on a handle ... from the hinges, we will provide twice the torque, so it will be twice as easy to open.