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प्रश्न
Which device is used to produce electricity? Describe with a neat diagram.
विकल्प
Electric motor
Galvanometer
Electric Generator (DC)
Voltmeter
उत्तर
Electric Generator (DC)
Explanation:
The device used for producing electricity is Electric generator (DC). It is based on the phenomenon of electromagnetic induction.
Working:
- The axle is rotated with a machine from outside. When the armature coil of the generator rotates in the magnetic field, electric potential difference is produced in the coil due to electromagnetic induction. This produces a current as shown by the glowing of the bulb or by a galvanometer. The direction of the current depends on the sense of rotation of the coil.
- In a DC generator, one brush is always in contact with the arm of the coil moving up while the other brush is in contact with the arm of the coil moving down in the magnetic field. Hence, the flow of the current in the circuit is always in the same direction and the current flows so long as the coil continues to rotate in the magnetic field.
- In this arrangement, brush A always remains in contact with the length moving up, whereas brush B always remains in contact with the length moving down. Here, split rings C and D act as a commutator. In this case, the direction of the current induced in the coil will be from M to T via N and S for the first half-rotation, and from T to M via S and N for the second half-rotation of coil MNST. Hence, we get a unidirectional current called direct current (DC).
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संबंधित प्रश्न
Draw figure ‘Electric motor’ and working
Name any four appliances where electric motor is used.
State whether the following statement is true or false.
An electric motor converts mechanical energy into electrical energy.
Name some devices in which electric motors are used
Explain the function of the following parts of an electric motor.
Armature
Explain the function of the following parts of an electric motor.
Brushes
Explain the function of the following parts of an electric motor.
Split ring
Label the four parts of an electric motor
Electric motor works on the magnetic effect of electric current.
A motor converts one form of energy into another. Name the two forms.
State whether the following statement is true or false:
An electric motor converts mechanical energy into electrical energy.
What is the function of a commutator in an electric motor made ?
Of what substance is the core of the coil of an electric motor made?
In an electric motor, which of the following remains fixed and which rotates with the coil?
Commutator ; Brush
What is the role of the spilt ring in an electric motor?
State what would happen to the direction of rotation of a motor if:
the current were reversed
State what would happen to the direction of rotation of a motor if:
In what ways can a motor be made more powerful?
In an electric motor, the direction of current in the coil changes once in each:
two rotations
one rotation
half rotation
one-four rotation
Tell the odd one out. Give proper explanation.
Loud speaker, Microphone, Electric motor, Magnet.
Name some of the devices in which electric motor are used.
Electric motor : converts electrical energy into mechanical energy : : Electric generator : _______
In which electric motor appliances do we use it?
Which of the following converts electrical energy into mechanical energy?
An electric motor converts ______.
State whether true or false. If false, correct the statement.
A generator converts mechanical energy into electrical energy.
State whether true or false. If false, correct the statement.
The speed of rotation of an electric motor can be increased by decreasing the area of the coil.
List the main parts of an electric motor.
An electric motor is a device which transforms ____________.
Material of the core of a strong magnet is ____________.
Draw a labelled circuit diagram of a simple electric motor and explain its working. In what way these simple electric motors are different from commercial motors?
Draw an appropriate schematic diagram showing common domestic circuits and discuss the importance of fuse. Why is it that a burnt out fuse should be replaced by another fuse of identical rating?
The moving part of an electric motor is called ______.
