Induced current from induced voltage: A coil has an induced voltage of 200 mV. A 120 Ω resistor is connected across the coil. Determine the induced current.

Introduction / Context:
Ohm’s law directly relates voltage, current, and resistance in a simple resistive load. When a coil produces an induced voltage and a resistor is connected across its terminals, the resulting current is set by I = V / R (ignoring coil resistance for this calculation, as typical in such questions).

Given Data / Assumptions:

• Induced voltage, V = 200 mV = 0.2 V.
• Load resistance, R = 120 Ω.
• Assume purely resistive load and negligible source impedance for this basic computation.

Concept / Approach:

Apply Ohm’s law: I = V / R. Be careful with milli- prefixes to avoid unit mistakes. The answer will be in amperes; convert to milliamperes for a convenient final value.

Step-by-Step Solution:

Verification / Alternative check:

Reverse check: V = I * R ≈ 1.7 mA * 120 Ω = 0.204 V (rounding explains slight difference), consistent with the given voltage.

Why Other Options Are Wrong:

120 mA would require 14.4 V across 120 Ω. 16 mA and 12 mA correspond to 1.92 V and 1.44 V, respectively—far larger than 0.2 V. 0.17 mA is off by a factor of 10 due to unit slip.

Common Pitfalls:

Not converting millivolts to volts, or misreading 200 mV as 2 V or 0.02 V. Always convert before dividing.

Final Answer:

1.7 mA