A heating coil is labelled $100\, W$, $220\, V$. The coil is cut in half and the two pieces are joined in parallel to the same source. The energy now liberated per second is .............. $J$
A$200$
B$400$
C$25$
D$50$
AIPMT 1995, Medium
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B$400$
b (b) When the heating coil is cut into two equal parts and these parts are joined in parallel, the resistance of coil is reduced to one fourth, so power consumed will become $4$ times i.e. $400\, Js^{-1}.$
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