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Give a scientific reason: For electric power transmission, copper or aluminium wire is used.

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प्रश्न

Give a scientific reason:

For electric power transmission, copper or aluminium wire is used.

कारण बताइए
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उत्तर

  1. Copper and aluminium have very low resistivity, hence less resistance for long wires.
  2. Low resistance causes less I2R heat loss, so energy loss is reduced.
  3. Both are good conductors that allow large currents to pass safely.
  4. Aluminium is lighter and cheaper, copper has higher conductivity; both are ductile and can be drawn into long wires.

Therefore, copper or aluminium wires are used to transmit electricity.

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अध्याय 4: Effects of electric current - Exercises [पृष्ठ ६१]

संबंधित प्रश्न

State four most common electrical appliances based on heating effect of electric current. Why do we use finely heated platinum wire in surgery?


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How does the resistance of a wire vary with its: 

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The current passing through a room heater has been halved. What will happen to the heat produced by it?


What is meant by the heating effect of current? Give two applications of the heating effect of current. 


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(a) magnitude of resistance of the resistor
(b) temperature of the resistor
(c) magnitude of current
(d) time for which current is passed


Give Scientific reason
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Heating effect of current is called ______


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Which of the following is correct?


Mark the correct choice

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  1. Will the bulb in the two circuits glow with the same brightness? Justify your answer.
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