Difficulty: Easy
Correct Answer: 14.4 V
Explanation:
Introduction / Context:
Voltage across a resistor is the product of current and resistance. This direct application of Ohm’s law appears constantly in biasing networks and sensor readouts, where small currents through kilo-ohm resistors create measurable voltages.
Given Data / Assumptions:
Concept / Approach:
Convert units carefully to maintain consistency, then multiply. Since both values are exact in this context, no rounding beyond standard decimal arithmetic is required.
Step-by-Step Solution:
Verification / Alternative check:
Using prefixes directly: 12 mA * 1.2 kΩ = (12 × 10^-3) * (1.2 × 10^3) = 14.4 × 10^0 = 14.4 V.
Why Other Options Are Wrong:
1.4 V and 10 V do not satisfy V = I * R with the given values; 100 V is far too large for milliampere currents through kilo-ohm resistances.
Common Pitfalls:
Mixing milli and kilo prefixes; dropping a power of ten; forgetting that volts scale linearly with both I and R.
Final Answer:
14.4 V
Discussion & Comments