ISCET DC Circuits Fundamentals Questions and Answers

Question 1

A technician measures a DC circuit with a 12V source and a single 100-ohm resistor. According to Ohm's Law, what is the expected current flowing through the circuit?

Accepted Answer

120 mA

Answer

1.2 A

Answer

8.33 mA

Answer

12 A

Question 2

In a DC series circuit containing three resistors (R1=10Ω, R2=20Ω, R3=30Ω), what is the total resistance (Rt)?

Accepted Answer

60 Ω

Answer

5.45 Ω

Answer

20 Ω

Answer

600 Ω

Question 3

A resistor has the following color bands: Yellow, Violet, Orange, and Gold. What is the nominal resistance and tolerance of this component?

Accepted Answer

47 kΩ ±5%

Answer

470 Ω ±10%

Answer

4.7 kΩ ±5%

Answer

47 kΩ ±10%

Question 4

According to Kirchhoff's Voltage Law (KVL), which of the following statements is true for any closed loop in a DC circuit?

Accepted Answer

The algebraic sum of all voltage drops and rises is zero.

Answer

The algebraic sum of the currents entering a node is zero.

Answer

The total power dissipated is equal to the total power supplied.

Answer

The equivalent resistance is the reciprocal of the sum of the reciprocals of individual resistances.

Question 5

A technician is troubleshooting a simple DC circuit with a lamp that fails to light up. A multimeter measurement across the power source shows the correct voltage. Which of the following is the MOST likely cause of the problem?

Accepted Answer

An open circuit in the wiring.

Answer

A short circuit across the lamp.

Answer

The resistance of the lamp is too high.

Answer

The power supply voltage is too low.

Question 6

Which circuit analysis theorem simplifies a complex linear circuit into an equivalent circuit consisting of a single voltage source in series with a single resistor?

Accepted Answer

Thevenin's Theorem

Answer

Norton's Theorem

Answer

Superposition Theorem

Answer

Ohm's Law