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प्रश्न
Study the following principle and answer the question.
A force is excreted on the current carrying conductor. The direction of this force depends on both the direction of the current and the direction of the magnetic field. This force is maximum when the direction of current is perpendicular to the direction of the magnetic field.
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.
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उत्तर
a. Fleming’s left hand rule
b. Electric motor

d. completed, the current flows through the coil in the direction A-B-C-D.
ii. The coil is in the magnetic field therefor according to Fleming’s left hand rule force exerted on the AB branch is in downward direction and on the CD branch it is in upward direction.
iii. After half rotation current in the coil start flowing through D-C-B-A direction.
iv. therefore, on DC branch force is in downward direction and BA branch it is in upward direction so its complete remaining half rotation.
In this way after every half rotation the direction of the current in the coil changes and coil continue to rotate.
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संबंधित प्रश्न
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An electric motor converts mechanical energy into electrical energy.
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In an electric motor, which of the following remains fixed and which rotates with the coil?
Commutator ; Brush
Fill in the following blank with suitable words:
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What is the principle of an electric motor?
In a d.c. motor, why must the current to the coil be reversed twice during each rotation?
State what would happen to the direction of rotation of a motor if:
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heat energy to electrical energy
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Name some of the devices in which electric motor are used.
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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.
An electric motor converts ______.
An electric motor is a device which transforms ____________.
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 ____________.
Commercial electric motors do not use ____________.
How can the speed of rotation of a coil be increased? Write at least three methods.
The moving part of an electric motor is called ______.
Define electric motor.
