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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
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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
What is the Principle of an Electric motor?
Name any four appliances where electric motor is used.
What is the role of the split ring in an electric motor?
State whether the following statement is true or false.
An electric motor converts mechanical energy into electrical energy.
Explain the construction and working of an electric motor.
Explain the function of the following parts of an electric motor.
Brushes
Label the four parts of an electric motor
Electric motor works on the magnetic effect of electric current.
State whether the following statement is true or false:
An electric motor converts mechanical energy into electrical energy.
Name the device which is used to reverse the direction of current in the coil of a motor?
Of what substance are the brushes of an electric motor made?
What is the role of the spilt ring in an electric motor?
Fill in the following blank with suitable words:
A motor contains a kind of switch called a .......... which reverses the current every half .......... .
What is the principle of an electric motor?
State what would happen to the direction of rotation of a motor if:
the current were reversed
What is an electric motor? With the help of a labelled diagram, describe the working of a simple electric motor
An electric motor is a device which transforms:
mechanical energy to electrical
heat energy to electrical energy
electrical energy to heat energy only
electrical energy to mechanical energy
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 : _______
Electric motors are devices that convert electrical energy into mechanical energy.
Observe the figure and write the answers to the questions asked.
- The construction shown in the figure is of which device?
- Explain the principle on which this device works.
- Write any three uses of this device.
Which of the following converts electrical energy into mechanical energy?
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.
In an electric motor, to make the coil rotating continuously in the same direction, the current is reversed in the coil after every half rotation by a device called ____________.
Commercial electric motors do not use ____________.
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?
How can the speed of rotation of a coil be increased? Write at least three methods.
Define electric motor.
Observe the following diagram and answer the questions.
- Construction of which equipment does the above diagram show?
- On which principle does this equipment work?
- According to which law the coil ABCD rotates?
- Write the law in your own words.
- Where is this equipment used?
