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प्रश्न
State three factors which govern the speed of rotation of an electric motor.
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उत्तर
(i) The strength of current in the coil,
(ii) The number of turns in the coil,
(iii) The strength of the magnetic field.
संबंधित प्रश्न
State two ways of magnetising an iron piece?
Name and state the rule by which polarity at the ends of a current carrying solenoid is determined.
State the two properties of the magnetic lines of force around a circular coil.
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How does a magnetic field set up by a solenoid change when number of turns are increased?
Why is soft iron generally used as the core of the electromagnet?
What energy conversion takes place during the working of a d c motor?
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.
Point out three differences between an electromagnet and a bar (or permanent) magnet.
State and explain Maxwell’s Cork Screw Rule.
