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प्रश्न
An electric bell has an electromagnet.
पर्याय
True
False
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उत्तर
This statement is True.
Explanation:
An electric bell has a piece of iron wound by a coil. When current passes through this coil, it behaves as an electromagnet.
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संबंधित प्रश्न
Fill in the following blank with suitable words:
The magnetic effect of a coil can be increased by increasing the number of ........... increasing the ........... or inserting an ........... core.
Fill in the following blank with suitable words:
If a coil is viewed from one end, and the current flows in a clockwise direction, then this end is a ........... pole.
Write the correct option by observing the figures.
Draw a neat labelled diagram to show the magnetic effect of electric current.
In the arrangement shown in Figure there are two coils wound on a non-conducting cylindrical rod. Initially the key is not inserted. Then the key is inserted and later removed. Then
Paheli does not have a night lamp in her room. She covered the bulb of her room with a towel at the night to get dim light. Has she taken the right step? Give one reason to justify your answer.
Boojho made an electromagnet by winding 50 turns of wire over an iron screw. Paheli also made an electromagnet by winding 100 turns over a similar iron screw. Which electromagnet will attract more pins? Give reason.
What do you mean by the magnetic effect?
Define the magnetic effect of electric current.
A student was asked to perform an experiment to study the force on a current carrying conductor in a magnetic field. He took a small aluminium rod AB, a strong horse shoe magnet, some connecting wires, a battery and a switch and connected them as shown. He observed that on passing current, the rod gets displaced. On reversing the direction of current, the direction of displacement also gets reversed. On the basis of your understanding of this phenomenon, answer the following questions:
- Why does the rod get displaced on passing current through it?
- State the rule that determines the direction of the force on the conductor AB.
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- If the U-shaped magnet is held vertically and the aluminium rod is suspended horizontally with its end B towards due north, then on passing current through the rod from B to A as shown, in which direction will the rod be displaced?
- Name any two devices that use current carrying conductors and magnetic fields.
OR
Draw the pattern of magnetic field lines produced around a current carrying straight conductor held vertically on a horizontal cardboard. Indicate the direction of the field lines as well as the direction of current flowing through the conductor.
