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प्रश्न
State the two properties of the magnetic lines of force around a circular coil.
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उत्तर
The important properties are:
(i) The magnetic lines of force near the wire are nearly circular, especially at the points where
the current enters or leaves the coil.
(ii) At the centre of the coil, the lines of force are almost parallel to each other, showing that the magnetic field at the centre or the coil may be considered uniform.
संबंधित प्रश्न
The diagram shows a coil wound around a U shape soft iron bar AB.
1) What is the polarity induced at the ends A and B when the switch is pressed?
2) Suggest one way to strengthen the magnetic field in the electromagnet
3) What will be the polarities at A & B if the direction of current is reversed in the circuit?
How will you make an iron bar electromagnet? Draw a diagram showing the polarities of the electromagnet?
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.
State three uses of an electromagnet?
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State two factors on which the magnitude of an induced e.m.f. in the secondary coils of a transformer depends.
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