Question

Why and where do we use left and right hand thumb rule?​

Answer 1

Answer:

If you point your thumb in the direction of the current, as shown, and let your fingers assume a curved position, the magnetic field circling around those wires flows in the direction in which your four fingers point. The Left Hand Rule shows what happens when an electrical current enters a magnetic field.

Prediction of direction of field (B), given that the current I flows in the direction of the thumb. A different form of the right-hand rule, sometimes called the right-hand grip rule, is used in situations where a vector must be assigned to the rotation of a body, a magnetic field or a fluid.