Question 1
A 12 V DC source is connected across a 100 Ω resistor. How much current flows in the circuit?
Show answer & explanation
Correct answer: C - 120 mA
10 exam-style questions with answers and explanations. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
These 10 free ESA questions are organized by exam domain, so you can see how each part of the Certified Electronics Systems Associate blueprint is tested. Reveal the answer and explanation under each question.
A 12 V DC source is connected across a 100 Ω resistor. How much current flows in the circuit?
Correct answer: C - 120 mA
Two resistors of 60 Ω and 30 Ω are connected in parallel. What is the total resistance of the combination?
Correct answer: D - 20 Ω
A resistor is marked with four color bands: brown, black, red, and gold. What are its resistance value and tolerance?
Correct answer: A - 1 kΩ, ±5%
In a series circuit containing three resistors, one resistor burns out and becomes an open. What happens to the current in the circuit?
Correct answer: B - It drops to zero
A 40 Ω resistor carries a steady current of 3 A. How much power does it dissipate?
Correct answer: D - 360 W
A sinusoidal AC voltage has a peak value of 170 V. What is its RMS (effective) value?
Correct answer: A - 120 V
As the frequency of the AC voltage applied to a capacitor increases, what happens to the capacitive reactance (Xc)?
Correct answer: B - It decreases
A series RLC circuit has R = 30 Ω, XL = 80 Ω, and Xc = 40 Ω. What is the total impedance (Z) of the circuit?
Correct answer: C - 50 Ω
In a series RLC circuit operating at its resonant frequency, which condition is true?
Correct answer: A - XL equals Xc, and impedance is at its minimum
A transformer has 400 turns on the primary and 100 turns on the secondary. If 240 V AC is applied to the primary, what is the secondary voltage?
Correct answer: B - 60 V
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