electric shock. This is called earthing. It is used as a safety measure in order to prevent electric shocks to the users. 5. State Fleming’s right Hand Rule. Give the principle, construction and working of the AC generator with a simple diagram. What modification will you suggest so that the output is DC Solution: It states that spread the forefinger and the middle finger of your right hand at right angle to one another in such a way that the forefinger points in the direction of magnetic field, thumb gives the direction of force, then the direction in which the middle finger points, gives the direction of induced current. Note: Draw the diagram given in your TB (generator) AC generator Principle: It works on the principle of electromagnetic induction, which states that electric current is induced in a closed circuit because of changing magnetic field. Construction: A generator consists of mainly four parts, namely coil, magnets, slip rings and brushes. Coil: A large number of insulated copper wires wound on a rectangular frame. Magnets: A permanent magnet to provide a strong a magnetic field. Slip rings: Two solid rings connected the two ends of the coil used to convey the current produced to outside circuit. Brushes: Two carbon brushes remain in sliding contact with slip rings. Working: The coil of the generator is rotated with the help of an axel. When coil rotates, it cuts through the magnetic of the magnet. So a current is induced in the coil by electromagnetic induction. The direction of this current is given by Fleming’s right hand rule. As the coil turns clockwise, arm AB moves up and arm CD goes down. The direction of the current is from A to B and C to D. When after half rotation CD starts going up and AB starts coming down, the direction of the current in the coil also reverses. Now it is from D to C and from B to A. This alternating current with the help of slip rings which are in sliding contact with brushes B1 and B2 is given out to the circuit. Hence the current produced by the generator is alternating and such a generator is called AC generator. To get direct current in of slip rings, split rings are used so that one brush is always in contact with the arm that goes downward. Then the current given out to the outer circuit is in the same direction. This type of generator is called DC generator. 6. How can you convert an A.C. into a D.C. generator?
electric shock. This is called earthing. It is used as a safety measure in order to prevent electric shocks to the users. 5. State Fleming’s right Hand Rule. Give the principle, construction and working of the AC generator with a simple diagram. What modification will you suggest so that the output is DC Solution: It states that spread the forefinger and the middle finger of your right hand at right angle to one another in such a way that the forefinger points in the direction of magnetic field, thumb gives the direction of force, then the direction in which the middle finger points, gives the direction of induced current. Note: Draw the diagram given in your TB (generator) AC generator Principle: It works on the principle of electromagnetic induction, which states that electric current is induced in a closed circuit because of changing magnetic field. Construction: A generator consists of mainly four parts, namely coil, magnets, slip rings and brushes. Coil: A large number of insulated copper wires wound on a rectangular frame. Magnets: A permanent magnet to provide a strong a magnetic field. Slip rings: Two solid rings connected the two ends of the coil used to convey the current produced to outside circuit. Brushes: Two carbon brushes remain in sliding contact with slip rings. Working: The coil of the generator is rotated with the help of an axel. When coil rotates, it cuts through the magnetic of the magnet. So a current is induced in the coil by electromagnetic induction. The direction of this current is given by Fleming’s right hand rule. As the coil turns clockwise, arm AB moves up and arm CD goes down. The direction of the current is from A to B and C to D. When after half rotation CD starts going up and AB starts coming down, the direction of the current in the coil also reverses. Now it is from D to C and from B to A. This alternating current with the help of slip rings which are in sliding contact with brushes B1 and B2 is given out to the circuit. Hence the current produced by the generator is alternating and such a generator is called AC generator. To get direct current in of slip rings, split rings are used so that one brush is always in contact with the arm that goes downward. Then the current given out to the outer circuit is in the same direction. This type of generator is called DC generator. 6. How can you convert an A.C. into a D.C. generator?
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