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प्रश्न
Name two factors on which the strength of magnetic field of an electromagnet depends and state how does it depend on the factors stated by you.
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उत्तर १
The strength of the magnetic field of an electromagnet depends on:
- Number of turns: The strength of the magnet increases with the number of turns of the winding in the solenoid.
- Current: The strength of the magnetic field increases with increasing current through the solenoid.
उत्तर २
Factors on which the strength of the magnetic field of an electromagnet depends are:
- The number of turns in the solenoid. If the number of turns in the solenoid increases or decreases, the magnetic intensity also increases or decreases.
- It is directly proportional to the strength of the current that flows in the turns of the solenoid.
- It is found to increase further if a soft iron piece, called core, is placed along the axis of the solenoid inside it.
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संबंधित प्रश्न
You are given an iron nail, a torch cell, and a long piece of insulated copper wire. With the help of a labelled neat diagram, describe in steps how you will make the nail, an electromagnet.
Name and state the rule by which polarity at the ends of a current carrying solenoid is determined.
Show with the aid of a diagram how a wire is wound on a U-shaped piece of soft iron in order to make it an electromagnet. Complete the circuit diagram and label the poles of the electromagnet.
Name the material used for making the armature of an electric bell. Give a reason for your answer.
Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
Electromagnet ______.
Describe briefly one way of producing an induced current in a coil. State one factor that determines the magnitude of induced e.m.f.
How does a magnetic field set up by a solenoid change when number of turns are increased?
What is dynomo (a.c. generator)? State the principle on which it works.
(i) A straight wire conductor passes vertically through a piece of cardboard sprinkled with iron filings. Copy the diagram and show the setting of iron filings when a current is passed through the wire in the upward direction and the cardboard is tapped gently. Draw arrows to represent the direction of the magnetic field lines.
(ii) Name the law which helped you to find the direction of the magnetic field lines.
How does a magnetic field set up by a solenoid change when cross-sectional area of solenoid is increased?
