Final answer:
The hot resistance of a 30.0-W headlight in a car with a 6.00-V electrical system is 1.20 Ω.
Step-by-step explanation:
To find the hot resistance of the headlight, we can use Ohm's law, which states that resistance (R) is equal to voltage (V) divided by current (I), or R = V/I. Given that the voltage is 6.00 V and the power is 30.0 W, we can use the formula P = IV to find the current. Rearranging the formula, we get I = P/V. Substituting the given values, we get I = 30.0 W / 6.00 V = 5.00 A. Now we can find the hot resistance by substituting the values into Ohm's law: R = 6.00 V / 5.00 A = 1.20 Ω.