Question

Difference between right hand thumb rule and left hand thumb rule

Answer 1

The Right-Hand Thumb Rule and Left-Hand Thumb Rule was developed by John Ambrose Fleming which is a type of visual mnemonics. The Right-Hand Rule applies to generators while the Left-Hand Rule applies to electric motors.The purpose of Right Hand Rule is to indicate the direction of induced current when a conductor moves in a magnetic field while the purpose of Left Hand Rule is to indicate the direction of motion in an electric motor.In Right Hand Rule, the Thumb represents the direction of Motion of the conductor, the First finger represents the direction of the Field and the Second finger represents the direction of the induced or generated current. In Left Hand Rule, the Thumb represents the direction of the thrust on the conductor, the First finger represents the direction of the Magnetic Field and the second finger represents the direction of the Current.

Answer 2

When A×B=C, then the direction of C is right angles to the plane having vectors A and B.

Right hand screw rule:- Let the first vector be A from where the right hand screw is rotated, and towards the vector B. So the direction in which the right handed screw is rotated gives the direction of C.

Right hand thumb rule:- Here the fingers of the right hand are curled from Vector A to B. Then the direction of erect thumb will give the direction of C.