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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.
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
Name any four appliances where electric motor is used.
Explain the construction and working of an electric motor.
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
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?
What is the other name of the split ring used in an electric motor?
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?
Fill in the following blank with suitable words:
Fleming's Rule for the motor effect uses the .......... hand.
Fill in the following blank with suitable words:
A motor contains a kind of switch called a .......... which reverses the current every half .......... .
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:
the current were reversed
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?
Which device is used to produce electricity? Describe with a neat diagram.
Name some of the devices in which electric motor are used.
Draw a labelled diagram of an electric motor.
Electric motor : converts electrical energy into mechanical energy : : Electric generator : _______
In which electric motor appliances do we use it?
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 ______.
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 ____________.
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?
How can the speed of rotation of a coil be increased? Write at least three methods.
The most suitable material for making permanent magnets is ______.
The moving part of an electric motor is called ______.
Define electric motor.
