Testing & TroubleshootingQuestion 508 of 521
In a series circuit, 24 V is applied across a 4 ohm and an 8 ohm resistor in series. What voltage will a DMM read across the 8 ohm resistor?
a.16 V
b.8 V
c.24 V
d.2 V
Explanation
Total R = 4 + 8 = 12 ohms, so I = 24 V / 12 ohms = 2 A. Across the 8 ohm resistor, V = I x R = 2 A x 8 ohms = 16 V (the 4 ohm drops the remaining 8 V). The larger series resistor drops the larger share of voltage.
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