CBT Electronic Fundamentals — Questions and Answers
Question 1: What is Ohm’s Law used to calculate in electrical circuits?
- Magnetic field strength
- Power factor
- Voltage, current, and resistance (Correct answer)
- Phase angle
Correct answer: Voltage, current, and resistance
Ohm’s Law describes the relationship between voltage (V), current (I), and resistance (R), defined as V = IR.
Question 2: What happens to total resistance when resistors are added in parallel?
- Total resistance increases
- Total resistance remains unchanged
- Total resistance becomes infinite
- Total resistance decreases (Correct answer)
Correct answer: Total resistance decreases
Adding resistors in parallel decreases the total resistance because the current has multiple paths to flow.
Question 3: Which unit is used to measure electrical capacitance?
- Ohms
- Henries
- Farads (Correct answer)
- Watts
Correct answer: Farads
Capacitance is measured in farads (F), representing the ability of a component to store electrical charge.
Question 4: What is the purpose of a diode in a circuit?
- Stores electrical energy
- Amplifies electrical signals
- Blocks all current flow
- Allows current to flow in one direction (Correct answer)
Correct answer: Allows current to flow in one direction
A diode allows current to flow in one direction only, acting as a one-way valve in electronic circuits.
Question 5: What is the role of inductance in an AC circuit?
- Reduces voltage
- Increases resistance
- Opposes changes in current (Correct answer)
- Filters noise signals
Correct answer: Opposes changes in current
Inductance resists changes in current and causes a phase shift between voltage and current in AC circuits.
Question 6: What kind of waveform is typically produced by an AC generator?
- Square wave
- Sawtooth wave
- Sinusoidal wave (Correct answer)
- Triangular wave
Correct answer: Sinusoidal wave
AC generators produce a sinusoidal waveform, which represents alternating current varying smoothly over time.
CBT Electronic Fundamentals
What is Ohm’s Law used to calculate in electrical circuits?