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प्रश्न
What is an electric motor?
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उत्तर
Electric motor : An electric motor is a device which converts the electrical energy into the mechanical energy.
संबंधित प्रश्न
Suppose you are given a long bar magnet and you are asked to break it into four small magnets. Draw diagrams showing the polarities of each broken part.
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 ______.
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.
Electromagnet ______.
State two factors on which the magnitude of an induced e.m.f. in the secondary coils of a transformer depends.
State the purpose of the iron core.
How does a magnetic field set up by a solenoid change when number of turns are increased?
State two advantages of an electromagnet over a bar magnet.
State the position of armature coil relative to the direction of magnetic field, in a D. C. motor when the deflecting couple acting and the coil is minimum.
What is dynomo (a.c. generator)? State the principle on which it works.
