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प्रश्न
What is an electromagnet?
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उत्तर
An electromagnet is a temporary strong magnet made from a piece of soft iron when current flows in the coil wound around it. It is an artificial magnet.
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संबंधित प्रश्न
Suppose you are given a long bar magnet and you are asked to break it into four small magnets. Draw diagrams showing the polarities of each broken part.
Tick the most appropriate answer.
Which of the following methods is used to magnetize a magnetic without touching it by a magnet?
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.
State two differences between an electromagnet and a permanent magnet.
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 ______.
State two factors on which the magnitude of an induced e.m.f. in the secondary coils of a transformer depends.
State two factors on which the strength of induced e. m.f. depends.
Describe a simple Experiment to demonstrate that there Exists a magnetic field around a current-carrying conductor.
How does a magnetic field set up by a solenoid change when a soft iron core is inserted inside solenoid?
State the condition when an electric charge can give rise to a magnetic field.
State the energy change that takes’place in a D. C. motor.
State the principle of a D. C. motor.
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.
A current-carrying solenoid is suspended so as to freely rotate in a horizontal plane. State in what direction will it rest. Give a reason for your answer.
or
When a solenoid that is carrying current is freely suspended, it comes to rest in a particular direction. Why does this happen?
(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.
State the function of a split ring in D.C. motor.
Which magnet will you use?
Iron is to be separated from trash.
Write the answer in your word.
How is an electromagnet made?
