explain in brief about electric motor and generator(construction,principal,working)
Answers
Electric motor:- converts electrical energy into mechanical energy
Principle:- whenever a current carrying conductor is placed in a magnetic field, it experiences a force and vice versa. The direction of force is given by Fleming's left hand rule.
Construction:- a rectangular coil ABCD is placed b/w the poles of a magnet. The current thru AB and CD are perpendicular to the field.
The ends A and B are connected to 2 halves P and Q of split ring ,they are also called commutator (a device which reverses direction of current ) the outer edges of a commutator r connected to brushes X and Y and the battery is connected across brushes ..
Working :- due to the battery , current flows thru ABCD placed in magnetic field.
Force acts in such a way that AB moves onwards and CD moves outwards.
For the loop to rotate continuously in one direction,the direction of current in CD should change.
This is done by commutator and the motion continues to be in one direction.
To make the motor more powerful, increase the no.of turns off loop, loop sound on soft iron, electromagnets can be used to create strong magnetic field.
Electric generator:- converts mechanical energy to electrical energy.
Principle:- electromagnetic induction
Construction:- coil ABCD placed b/w 2 poles of a permanent magnet.
Ends of the coil connected to rings R1 and R2 . R1 is connected to brush B1 and R2 to B2 ,. B1 and BE connected to galvanometer.
Working:- AB moves up and CD moves down (inwards). According to Fleming's right hand rule, current moves from AB to CD and from brush B1 to B2.
So the current changes it's direction therefore an alternative current (AC) is produced.