A) 50 J
B) 40 J
C) 4000 J
D) 400 J
Correct Answer: D
Solution :
The coil is cut into two equal halves, then resistance of each part\[=\frac{R}{2}\] If the both part are joined in parallel, then resistance \[R'=\frac{R}{4}\] The energy per second \[P=\frac{{{V}^{2}}}{R}\] Or \[P\propto \frac{1}{R}\] \[\frac{P'}{P}=\frac{R}{R'}=4\] \[P'=4P=400J/s\]You need to login to perform this action.
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