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Question
Two resistors A and B of 4 Ω and 6 Ω respectively are connected in parallel. The combination is connected across a 6 volt battery of negligible resistance. Calculate the power supplied by the battery.
Solution
Given,
Resistance, RA = 4 Ω
Resistance, RB = 6 Ω
Voltage, V = 6 V
Ω As resistances are connected in parallel
Equivalent Resistance = `1/"R" = 1/"R"_"A" + 1/"R"_"B"`
`1/"R" = 1/4 + 1/6`
= `10/24`
= `5/12`
R = 2.4 Ω
As power, P = `"V"^2/"R"`
= `(6)^2/2.4`
= 15 W
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