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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.
Name the type of transformer shown in fig . What changes will you observe regarding the brightness of the lamp, if
(a) The no. of turns in the secondary is doubled?
(b) The part X of the transformer is removed?
( c) The core of the transformer is made out of copper?
(d ) The A.C. supply is replaced by D.C.?
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 ______.
The magnetic flux through a coil having 100 turns decreases from 5 milli weber to zero in 5 second. Calculate the e.m.f. induced in the coil.
A straight current-carrying conductor is kept in a magnetic field. It Experiences a force. State three factors on which the magnitude of force Experienced by the conductor depends. Under what condition will the conductor Experience no force?
State the principle of a D. C. motor.
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?
State and explain Maxwell’s Cork Screw Rule.
State the function of a split ring in D.C. motor.
How does a magnetic field set up by a solenoid change when cross-sectional area of solenoid is increased?
