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प्रश्न
Draw figure ‘Electric motor’ and working
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उत्तर
Electric motor:
Working: When a current is allowed to flow through the coil MNST by closing the switch, the coil starts rotating anti-clockwise. This happens because a downward force acts on length MN and at the same time, an upward force acts on length ST. As a result, the coil rotates anti-clockwise.
Current in the length MN flows from M to N and the magnetic field acts from left to right, normal to length MN. Therefore, according to Fleming’s left hand rule, a downward force acts on the length MN. Similarly, current in the length ST flows from S to T and the magnetic field acts from left to right, normal to the flow of current. Therefore, an upward force acts on the length ST. These two forces cause the coil to rotate anti-clockwise.
After half a rotation, the position of MN and ST interchange. The half-ring D comes in contact with brush A and half-ring C comes in contact with brush B. Hence, the direction of current in the coil MNST gets reversed.
The current flows through the coil in the direction TSNM. The reversal of current through the coil MNST repeats after each half rotation. As a result, the coil rotates unidirectional.
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संबंधित प्रश्न
What is the Principle of an Electric motor?
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
Label the four parts of an electric motor
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?
Fill in the following blank with suitable words:
Fleming's Rule for the motor effect uses the .......... hand.
What is the principle of an electric motor?
State what would happen to the direction of rotation of a motor if:
both current and magnetic field were reversed simultaneously.
State what would happen to the direction of rotation of a motor if:
In what ways can a motor be made more powerful?
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
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Loud speaker, Microphone, Electric motor, Magnet.
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a) By which law we can determine the direction of force excreted on the current carrying conductor.
b) In which electrical equipment this principle is used.
c) Draw a diagram representing construction of this equipment.
d) Write the working of this equipment in brief.
Draw a labelled diagram of an electric motor.
Electric motor : converts electrical energy into mechanical energy : : Electric generator : _______
Electric motors are devices that convert electrical energy into mechanical energy.
What is an electric motor?
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.
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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.
Direction of rotation of a coil in electric motor is determined by ____________.
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 ____________.
Material of the core of a strong magnet is ____________.
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 ______.
Define electric motor.
