Questions and answers for exam Preparation

MCQs

Total Questions : 480 | Page 46 of 48 pages

Question 451. Which one of the following statements is true for the impedance of a series RC circuit?

The impedance is greater than the sum of the resistance and capacitive reactance
The impedance is equal to the sum of the resistance and capacitive reactance
The impedance is greater than either the resistance or capacitive reactance but less than their sum
The impedance is less than the sum of the resistance and capacitive reactance
None of the above

Discuss Question

Answer: Option C. -> The impedance is greater than either the resistance or capacitive reactance but less than their sum

Question 452. What is the inductive reactance of a 0.1-H coil that is operating at 1000 Hz?

100 Ohm
Less than 1 Ohm
628 Ohm
444 Ohm
None of the above

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Answer: Option C. -> 628 Ohm

Question 453. What is the turns ratio of a power transformer that shows 50 V at its secondary winding when you apply 150 V to its primary winding?

01-Apr
01-Mar
2
3
None of the above

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Answer: Option D. -> 3

Question 454. Which one of the following is a statement of KirchhofFs voltage law?

The total voltage in a parallel circuit is less than the value of the smallest voltage
The algebraic sum of voltages in a loop is equal to zero
The voltage drop across a resistance is proportional to the value of resistance and the amount of current flowing through it
The algebraic sum of voltages entering and leaving a point is equal to zero
None of the above

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Answer: Option B. -> The algebraic sum of voltages in a loop is equal to zero

Question 455. If a transistor operates at the middle of the load line, an increase in the current gain will move the Q point

down
up
nowhere
off the load line
None of the above

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Answer: Option B. -> up

Question 456. Which one of the following statements regarding ac circuits is correct?

Current and voltages are in phase through a resistor
Current leads the voltage through a resistor
Current lags the voltage through a resistor
All of the above
None of the above

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Answer: Option A. -> Current and voltages are in phase through a resistor

Question 457. What are the main parts of an atom?

Protons only
Electrons, protons, and ions
Electrons, ions, and neutrons
Electrons, protons, and neutrons
None of the above

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Answer: Option D. -> Electrons, protons, and neutrons

Question 458. A real voltage source has

Zero internal resistance
Infinite internal resistance
A small internal resistance
A large internal resistance
None of the above

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Answer: Option C. -> A small internal resistance

Question 459. Which one of the following statements most accurately describes the nature of inductive reactance?

Inductive reactance is an opposition to current flow in dc circuits
Inductive reactance is an opposition to current flow in ac circuits
Inductive reactance is another term for counter emf
Inductive reactance is a force that tends to overcome the effects of counter emf
None of the above

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Answer: Option B. -> Inductive reactance is an opposition to current flow in ac circuits

Question 460. Current is