Find current through a series string: a 12 V battery is connected across resistors of 68 Ω, 47 Ω, 220 Ω, and 33 Ω in series. What is the circuit current in milliamperes (mA)?

Introduction / Context:
Determining series current requires computing the total equivalent resistance and then applying Ohm’s law. This is fundamental in sizing sources and predicting voltage drops for component networks in DC circuits.

Given Data / Assumptions:

• Source: 12 V battery.
• Resistors in series: 68 Ω, 47 Ω, 220 Ω, 33 Ω.
• Ideal components; DC steady state.

Concept / Approach:

Total series resistance is the sum. Current I = V / R_total. Convert the final answer to mA for readability if needed (1 A = 1000 mA).

Step-by-Step Solution:

Verification / Alternative check:

Power sanity check: P = V * I ≈ 12 * 0.0326 ≈ 0.391 W total, plausible for small resistors.

Why Other Options Are Wrong:

16.3 mA would require roughly double the resistance. 163 mA or 326 mA imply much smaller total resistance than 368 Ω.

Common Pitfalls:

Mistakes in arithmetic while summing resistors; forgetting to convert A to mA for the final expression.

Final Answer:

32.6 mA