An 8 Ω resistor carries 1.5 A. Which option gives the correct voltage across it and the power dissipated?

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Multiple Choice

An 8 Ω resistor carries 1.5 A. Which option gives the correct voltage across it and the power dissipated?

Explanation:
Voltage, current, and resistance are linked by Ohm’s Law: V = IR, and power by P = VI (also P = I^2R or P = V^2/R). With R = 8 Ω and I = 1.5 A, the voltage is V = 1.5 × 8 = 12 V. The power dissipated is P = VI = 12 × 1.5 = 18 W (also P = I^2R = (1.5)^2 × 8 = 18 W). The given current fixes both voltage and power to these values; the other options would require different current or resistance to hold, so they don’t match both quantities.

Voltage, current, and resistance are linked by Ohm’s Law: V = IR, and power by P = VI (also P = I^2R or P = V^2/R). With R = 8 Ω and I = 1.5 A, the voltage is V = 1.5 × 8 = 12 V. The power dissipated is P = VI = 12 × 1.5 = 18 W (also P = I^2R = (1.5)^2 × 8 = 18 W). The given current fixes both voltage and power to these values; the other options would require different current or resistance to hold, so they don’t match both quantities.

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