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An automobile headlight has 2.50 A flowing through it when 12.0 V is applied across it. What is its resistance?
A30.0 ohm
B0.208 ohm
C4.80 ohm
D9.50 ohm
Answer & Solution
Correct answer: C. 4.80 ohm
1. Ohm's law gives V = IR, so R = V / I.
2. Substitute the given values: R = 12.0 V / 2.50 A.
3. R = 4.80 ohm.
_Source: OpenStax Physics (CC BY 4.0), Ch 19 "Electrical Circuits", section Resistance of a Headlight_
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