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प्रश्न
State two advantages of an electromagnet over a permanent magnet.
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उत्तर
- An electromagnet can produce a strong magnetic field.
- The strength of the magnetic field of an electromagnet can easily be changed by changing the current in its solenoid.
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संबंधित प्रश्न
The force on a north pole, `vecF = mvecB` , parallel to the field `vecB` . Does it contradict our earlier knowledge that a magnetic field can exert forces only perpendicular to itself?
If the current is doubled, the deflection is also doubled in
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(a) P1 and P2
(b) Q1 and Q2
(c) P1 and Q1
(d) P2 and Q2
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Answer in brief.
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