Trắc nghiệm Công nghệ 12 Điện - điện tử Cánh diều bài 1: Khái quát về kĩ thuật điện
1. What is the term for the opposition to the flow of electric current in a circuit?
A. Conductance
B. Capacitance
C. Resistance
D. Inductance
2. What is the primary difference between AC and DC circuits?
A. AC circuits use transistors, while DC circuits use vacuum tubes.
B. AC current changes direction periodically, while DC current flows in one direction.
C. AC circuits are always high voltage, while DC circuits are always low voltage.
D. AC circuits are used for batteries, while DC circuits are used for power grids.
3. What is the unit of electrical resistance?
A. Ampere (A)
B. Volt (V)
C. Ohm (Ω)
D. Hertz (Hz)
4. What is the main application of semiconductors in electronics?
A. To generate heat.
B. To conduct electricity with very high resistance.
C. To control the flow of electricity and amplify signals.
D. To store mechanical energy.
5. What does the term "frequency" refer to in AC circuits?
A. The amplitude of the voltage wave.
B. The number of cycles of the alternating current per second.
C. The phase difference between voltage and current.
D. The total power consumed by the circuit.
6. Which electrical quantity is measured in Volts (V)?
A. Resistance
B. Current
C. Power
D. Voltage
7. Which branch of electrical engineering deals with the study and application of electric charges at rest?
A. Electromagnetics
B. Electrostatics
C. Electronics
D. Power Systems
8. Which unit is used to measure electric current?
A. Ohm (Ω)
B. Volt (V)
C. Ampere (A)
D. Watt (W)
9. What is the primary function of a transformer?
A. To convert DC voltage to AC voltage.
B. To change the frequency of an AC signal.
C. To step up or step down AC voltage levels.
D. To store large amounts of electrical energy.
10. Which type of electrical current flows in only one direction?
A. Alternating Current (AC)
B. Direct Current (DC)
C. Pulsating Direct Current
D. Variable Current
11. What does the term "conductance" represent in electrical terms?
A. The opposition to current flow.
B. The reciprocal of resistance, indicating ease of current flow.
C. The storage of energy in an electric field.
D. The rate at which energy is transferred.
12. What is the basic unit of electrical power?
A. Joule (J)
B. Watt (W)
C. Volt-Ampere (VA)
D. Ohm (Ω)
13. Which of the following is a fundamental concept in electrical engineering?
A. Newton"s laws of motion.
B. Ohm"s Law, relating voltage, current, and resistance.
C. The principles of aerodynamics.
D. The theory of relativity.
14. Which component converts electrical energy into mechanical energy?
A. Generator
B. Motor
C. Transformer
D. Battery
15. Which law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all physical conditions remain constant?
A. Kirchhoff"s Voltage Law
B. Ampere"s Law
C. Ohm"s Law
D. Faraday"s Law of Induction
16. What is the primary role of a generator?
A. To store electrical energy in a magnetic field.
B. To convert mechanical energy into electrical energy.
C. To regulate voltage in a circuit.
D. To transform AC to DC.
17. What is the function of a resistor in an electrical circuit?
A. To store electrical energy.
B. To amplify the electrical signal.
C. To limit or control the flow of current.
D. To convert electrical energy into light.
18. What is the main component that converts chemical energy into electrical energy?
A. Capacitor
B. Inductor
C. Battery
D. Resistor
19. In a parallel circuit, how does the total voltage compare to the voltage across each branch?
A. The total voltage is the sum of voltages across each branch.
B. The total voltage is less than the voltage across the smallest branch.
C. The voltage across each branch is the same as the total voltage.
D. The total voltage is the reciprocal of the voltage across each branch.
20. Which of the following electrical components stores electrical energy in an electric field?
A. Inductor
B. Capacitor
C. Resistor
D. Diode
21. What is the primary role of electrical engineering in modern society?
A. To design and maintain systems that generate, transmit, and utilize electrical energy.
B. To develop software applications for personal computers.
C. To conduct research in biological sciences and medicine.
D. To manage financial markets and economic policies.
22. What is a common application of electrical engineering in communication systems?
A. Designing bridges and buildings.
B. Developing telecommunication networks and signal processing.
C. Creating agricultural machinery.
D. Studying geological formations.
23. In a series circuit, how does the total resistance compare to individual resistances?
A. The total resistance is less than any individual resistance.
B. The total resistance is equal to the smallest individual resistance.
C. The total resistance is the sum of all individual resistances.
D. The total resistance is the reciprocal of the sum of individual resistances.
24. What does the term "voltage" represent in an electrical circuit?
A. The rate of flow of electric charge.
B. The opposition to the flow of electric current.
C. The electric potential difference between two points.
D. The amount of electrical power consumed.
25. Which of the following is a key characteristic of electrical circuits used in modern electronics?
A. They exclusively use mechanical switches.
B. They often involve complex arrangements of semiconductor devices.
C. They are designed to be as large and heavy as possible.
D. They operate using only direct current.
