In the air, there's nothing holding the body of the helicopter still - so the rotor blades spin one direction, but the torque applied to spin the rotors tries to spin the body of the helicopter in the opposite direction. The little rotor on the tail helps keep the body of the helicopter pointed in the same direction.

Recently we're working to degrade accounts with 0 contributions from creator to learner. If you're a learner and very keen to be a creator, you must keep posting interesting questions and contact to admins from the Facebook Group of Mattrab Community. For being an admin, you must be in grade 12, either completed or recently enrolled, your notes, and all your records and contributions will be verified for that

The Wheatstone bridge is not suitable for measuring very low resistance because it is based on a ratio of two resistances, and the resolution of the bridge decreases as the ratio approaches 1. This means that the Wheatstone bridge is not accurate enough to measure very small changes in resistance.