A) 10 W
B) 20 W
C) 40 W
D) 100 W
Correct Answer: A
Solution :
[a] Resistance of bulb \[=\frac{{{V}^{2}}}{P}=\frac{200\times 200}{40}=1000\Omega \] New power\[=\frac{{{V}^{2}}}{R}=\frac{100\times 100}{1000}=10W.\]You need to login to perform this action.
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