The specification on a heater coil is 250 V, 500 W. Calculate the resistance of the coil. What will be the resistance of a coil of 1000 W to operate at the same voltage.


Let the resistance of the coil be R


Given


voltage =250 V


power =500 W



The power P consumed by a coil of resistance R when connected across a supply V is given by Joule’s heating effect -






Now when, P = 1000 W





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