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प्रश्न
principle of an electric motor ?
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उत्तर
Principle: An electric motor (dc motor) works on the principle that when an electric current is passed through a conductor placed normally in a magnetic field, a force acts on the conductor as a result of which the conductor begins to move and mechanical energy is obtained.
संबंधित प्रश्न
State two differences between an electromagnet and a permanent magnet.
What is an electric motor?
Name the material of core in (a) an electric bell, (b) electromagnet, (c) a d.c. motor, (d) an a.c. generator and (e) a transformer.
Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
Electric bell ______.
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State the energy change that takes’place in a D. C. motor.
State important properties (or characteristics) of magnetic lines of force around a straight conductor.
A current-carrying solenoid is suspended so as to freely rotate in a horizontal plane. State in what direction will it rest. Give a reason for your answer.
or
When a solenoid that is carrying current is freely suspended, it comes to rest in a particular direction. Why does this happen?
How does a magnetic field set up by a solenoid change when cross-sectional area of solenoid is increased?
Which magnet will you use?
Iron is to be separated from trash.
