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प्रश्न
Explain the magnetic field created by a current around a conductor from the figure.
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उत्तर
- Consider a circuit connected as shown in the figure.

- A cardboard is placed around a thick copper wire. A magnetic needle is used to check the magnetic field around the wire.
- When a large current flows through the thick wire, the magnetic needle shows deflection. At different points on the cardboard, the needle points in different directions.
- When joined the directions shown by the needle, the lines formed indicate that the magnetic field produced around a current-carrying conductor is in the form of concentric circles.
- The deflection in the needle changes according to the current in the conductor. For a given current, if we move the compass needle away from the wire, its deflection decreases.
- The direction of the magnetic field formed around the conductor depends on the direction of the current and is given by the right-hand thumb rule.
- If the thumb of the right hand indicates the direction of the current then, the curled fingers indicate the direction of the magnetic field formed.
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संबंधित प्रश्न
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- length of the rod AB is increased?
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Observe the following diagram and choose the correct alternative:

Read the given passage and answer the following questions:
The home electrical connection consists of ‘live’, ‘neutral’ and ‘earth’ wires. The ‘live’ and the ‘neutral’ wires have potential difference of 220 V. The ‘earth’ is connected to ground. Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives a way the two wires come in contact with each other and a large current flows through it producing heat. If any inflammable material (such as wood, cloth, plastic, etc.) exists around that place it can catch fire. Therefore a fuse wire is used as a precautionary measure.
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- What is a short circuit?
- Write the function of a fuse.
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Magnetic effect of current was discovered by ______.
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HTRCO
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______ cells cannot be recharged after use.
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- 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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