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Question
The figure given below shows the magnetic field around the conductor. Study it and answer the questions:

- What changes are caused by increasing current?
- What do you see when the magnetic needle is kept a little away from the wire?
- In the second part of the figure, the iron filings arrange themselves in a circular manner around the wire. Why does this happen?
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Solution
- If the current through the wire is increased, the intensity of the magnetic field also increases.
- It starts deflecting less when the magnetic needle is kept away from the wire.
- The iron fillings get magnetised and arrange themselves in a circular manner around the wire.
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