1. The primary property of an inductor is to:
A. Store energy in an electric field
B. Store energy in a magnetic field
C. Resist the flow of current
D. Amplify voltage
Answer: B. Store energy in a magnetic field
2. The SI unit of inductance is:
A. Tesla
B. Henry
C. Weber
D. Farad
Answer: B. Henry
3. Inductors oppose changes in:
A. Voltage
B. Current
C. Power
D. Resistance
Answer: B. Current
4. The inductance of a coil depends on:
A. Number of turns of the coil
B. Core material
C. Cross-sectional area of the coil
D. All of the above
Answer: D. All of the above
5. What is the self-inductance of a coil?
A. The property of a coil to store energy in the form of an electric field
B. The property of a coil to oppose changes in its own current
C. The property of a coil to conduct current
D. The resistance of the coil
Answer: B. The property of a coil to oppose changes in its own current
6. In an ideal inductor, the phase difference between voltage and current is:
A. 0°
B. 45°
C. 90°
D. 180°
Answer: C. 90°
7. In an inductor, the induced voltage is proportional to:
A. The resistance of the coil
B. The rate of change of current
C. The applied current
D. The capacitance of the circuit
Answer: B. The rate of change of current
8. The energy stored in an inductor is given by:
A. W=12LI2W = \frac{1}{2} L I^2
B. W=L×IW = L \times I
C. W=12LV2W = \frac{1}{2} L V^2
D. W=12CV2W = \frac{1}{2} C V^2
Answer: A. W=12LI2W = \frac{1}{2} L I^2
9. Inductors are commonly used in:
A. High-pass filters
B. Low-pass filters
C. Band-pass filters
D. All of the above
Answer: D. All of the above
10. The primary function of an inductor in a transformer is to:
A. Increase current
B. Store energy temporarily
C. Couple energy between two circuits
D. Convert DC to AC
Answer: C. Couple energy between two circuits
11. In a DC circuit, the inductor behaves like:
A. A short circuit
B. An open circuit
C. A resistor
D. A capacitor
Answer: A. A short circuit
12. Inductors are used in electric motors to:
A. Increase speed
B. Reduce power loss
C. Generate a magnetic field
D. Decrease current
Answer: C. Generate a magnetic field
13. Which of the following applications uses inductors?
A. Radio tuning circuits
B. Power supply filters
C. Energy storage in DC-DC converters
D. All of the above
Answer: D. All of the above
14. Inductors in series result in:
A. Increased total inductance
B. Decreased total inductance
C. The same inductance as a single inductor
D. Zero inductance
Answer: A. Increased total inductance
15. In AC circuits, inductors are used to:
A. Block AC signals
B. Impede changes in AC current
C. Rectify current
D. Amplify current
Answer: B. Impede changes in AC current