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प्रश्न
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.
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उत्तर
The deflecting couple acting on the coil is minimum when the plane of the coil is normal to the direction of magnetic field.
संबंधित प्रश्न
State three uses of an electromagnet?
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.
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.?
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State the factors that can increase the speed of rotation of the coil in a D.C. motor.
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State the function of a split ring in D.C. motor.
Write the answer in your word.
How is an electromagnet made?
