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Question
A car headlight bulb working on a 12 V car battery draws a current of 0.5 A. The resistance of the light bulb is:
Options
0.5 Ω
6 Ω
12 Ω
24 Ω
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Solution
24 Ω
Explanation:
Voltage, V = 12 V
Current, I = 0.5 A
Resistance, R = `"Voltage"/"Current"`
= `V/I`
= `12/0.5`
= 24 Ω
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