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Question
A car bulb connected to a 12 volt battery draws 2 A current when glowing. What is the resistance of the filament of the bulb? Will the resistance be more same or less when the bulb is not glowing?
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Solution
Potential Difference/Voltage (V) = 12 V
Current (I) = 2 A
Resistance (R) = ?
According to Ohm's Law:
V = IR
Then R = `"V"/"I"`
R = `12 / 2`
R = 6 Ω
Resistance will be less when the bulb is not glowing.
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