Current Electricity - Result Question 84
89. 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
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======= ####89. 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
c3eec34ec6b1fad69db54a20ad4b2dca40c2aa54 (a) $25 J$
(b) $50 J$
(c) $200 J$
(d) $400 J$
[1995]
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Answer:
Correct Answer: 89. (d)
Solution:
- (d) Power of heating coil $=100 W$ and voltage (V) $=220$ volts. When the heating coil is cut into two equal parts and these parts are joined in parallel, then the resistance of the coil is reduced to one-fourth of the previous value. Therefore energy liberated per second becomes 4 times i.e., $4 \times 100=400 J$.
