Physics
What is meant by electrical resistance of a conductor? State how resistance of a conductor is affected when
(a) a low current passes through it for a short duration and
(b) a heavy current passes through it for about 30 s.
Current Electricity
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Answer
The obstruction offered to the flow of current by a conductor is called it's electrical resistance.
(a) When a low current is passed through the conductor for a short duration there will be no change in the temperature of the conductor and so the resistance of the conductor will remain same.
(b) When a high amount of current is passed through a conductor for 30 s then it will raise the temperature of the conductor and due to an increase in temperature resistance of the conductor will also increase.
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