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प्रश्न
Point out three differences between an electromagnet and a bar (or permanent) magnet.
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उत्तर
| Electromagnet | Bar Magnet |
| 1. An electromagnet exhibits a much stronger magnetic field. | A bar magnet is not able to exhibit a strong magnetic field. |
| 2. Its polarity can be reversed by reversing the direction of current flowing in the turns of the coil (or solenoid). | Its polarity is fixed. |
| 3. It is a temporary magnet, it behaves as a magnet only when the current flows through the solenoid. | It is a permanent magnet and cannot be readily demagnetized. |
संबंधित प्रश्न
Name and state the rule by which polarity at the ends of a current carrying solenoid is determined.
State three uses of an electromagnet?
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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.
State the condition when an electric charge can give rise to a magnetic field.
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 an the coil is maximum.
What are the factors that govern the magnitude of force acting on a current carrying conductor which is freely suspended in a magnetic field?
Write the answer in your words.
How is an electromagnet made?
