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Question
The voltage across a 3Ω resistance is 6 V. How large is the current? What is
the resistance of a filament lamp when a voltage of 3 V across it causes a
current of 0.5 A?
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Solution
If voltage, V = 6 volt and resistance R = 3Ω
The a/c to ohm's law, current I = `"V"/"R" = 6/3 = 2 "A"`
For filament lamp:
Given that, voltage= 3 V, current= 0.5 A.
let R be the resistance of the filament lamp;
then R = `"V"/"I" = 3/0.5` = 6Ω
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