Branch Circuits & WiringQuestion 197 of 521
The internal cross-sectional area of 1/2" EMT is 0.304 in³ per Table 4. For three or more conductors, what usable fill area (40%) is available?
a.0.122 in²
b.0.094 in²
c.0.161 in²
d.0.304 in²
Explanation
0.304 × 0.40 = 0.122 in². The 31% (two-conductor) area would be 0.094 in² and the 53% (single-conductor) area would be 0.161 in²; 0.304 is the full 100% area.
Law Reference: 2023 NEC Chapter 9, Table 4Practice all 521 questions free — no signup required.
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