What is meant by "electrical resistance" of a conductor ? State how resistance of a conductor is affected when $(i)$ a low current passes through it for a short duration; $(ii)$ heavy current passes through it for about $30$ seconds.
What is meant by "electrical resistance" of a conductor ? State how resistance of a conductor is affected when $(i)$ a low current passes through it for a short duration; $(ii)$ heavy current passes through it for about $30$ seconds.
Electrical resistance is the opposition offered to the flow of current by the conductor.
$(i)$ The resistance will remain the same as a low current passes through it for a short duration.
$(ii)$ The resistance will increase when a heavy current passes through it for about $30$ min. This is because resistance depends directly on the temperature of the conductor, and heavy current will heat up the conductor.
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