Explore topic-wise MCQs in Engineering.

This section includes 4320 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.

3951.

1 Microfarad is the same as:

A. 1 millionth of a picofarad
B. 1000 millifarads
C. 1 million picofarads
D. 1 million farads
E. None of the above
Answer» D. 1 million farads
Discussion
3952.

Which one of the following statements is true for resistance in a parallel circuit?

A. The total resistance is equal to the sum of the individual resistances in a parallel circuit.
B. The total resistance of a parallel circuit is always less than the value of the smallest resistance
C. The total resistance of a parallel circuit is equal to the total voltage
D. The total resistance in a parallel circuit is equal to the average value of the individual resistances
E. None of the above
Answer» C. The total resistance of a parallel circuit is equal to the total voltage
Discussion
3953.

The direction of conventional current flow is:

A. from negative to positive
B. from positive to negative
C. from left to right
D. from neutral to positive
E. None of the above
Answer» C. from left to right
Discussion
3954.

Doubling the operating frequency of a purely inductive circuit:

A. doubles the amount of current through the inductors
B. has no effect on the current through the inductors
C. cuts the current through the inductors one-half
D. increases the current, but by an amount that can be determined only by doing a complete analysis of the circuit
E. None of the above
Answer» D. increases the current, but by an amount that can be determined only by doing a complete analysis of the circuit
Discussion
3955.

The secondary voltage for a certain power transformer is twice the voltage applied to the primary. The current flowing in the secondary winding will be:

A. One-half the primary current
B. Same as the primary current
C. Twice the primary current
D. No more than 10% less than the primary current
E. None of the above
Answer» B. Same as the primary current
Discussion
3956.

How many protons does the nucleus of a silicon atom contain?

A. 4
B. 29
C. 14
D. 48
E. None of the above
Answer» D. 48
Discussion
3957.

Suppose the peak value of a sinusoidal voltage is 50 V. What is the rms value?

A. 37.4 V
B. 35.4 V
C. 38.74 V
D. 30.4 V
E. None of the above
Answer» C. 38.74 V
Discussion
3958.

What is the difference between a conductor and an insulator?

A. A conductor allows current to flow much easier than an insulator does
B. An insulator has an excessive number of free electrons, while a conductor has a few free electrons or none at all
C. An insulator allows current to flow much easier than a conductor does
D. The difference between conductors and insulators depends on how they are used
E. None of the above
Answer» B. An insulator has an excessive number of free electrons, while a conductor has a few free electrons or none at all
Discussion
3959.

A circuit has two different voltage sources that are connected in a series-aiding form. If the sources are rated at 6 V and 9 V, what is the total source voltage?

A. 15 V
B. 16 V
C. 7.5 V
D. 8 V
E. None of the above
Answer» B. 16 V
Discussion
3960.

At room temperature an intrinsic semiconductor has

A. a few free electrons and holes
B. many holes
C. many free electrons
D. No holes
E. None of the above
Answer» B. many holes
Discussion
3961.

If a load resistance is 1 kW, a stiff voltage source has a resistance of

A. At least 10 Ohm
B. less than 10 Ohm
C. More than 100 k Ohm
D. Less than 100 k Ohm
E. None of the above
Answer» C. More than 100 k Ohm
Discussion
3962.

A typical light switch in your home is a:

A. knife switch
B. toggle switch
C. rotary switch
D. momentary push button switch
E. None of the above
Answer» C. rotary switch
Discussion
3963.

Suppose the voltage from a power outlet is 120 Vrms. What is the peak voltage?

A. 100 V
B. 120 V
C. 170 V
D. 180 V
E. None of the above
Answer» D. 180 V
Discussion
3964.

A device that converts thermal energy to electrical energy is called a:

A. thermocouple
B. solar cell
C. chemical cell
D. piezoelectric devices
E. None of the above
Answer» B. solar cell
Discussion
3965.

How much power is being dissipated by a 1000 W resistance that has 25 V applied to it?

A. 0.24 W
B. 0.625 W
C. 80 W
D. 325 kW
E. None of the above
Answer» C. 80 W
Discussion
3966.

When operating above its resonant frequency, a parallel RLC circuit has the characteristics of a:

A. parallel RL circuit
B. parallel RC circuit
C. parallel RLC circuit operated above its resonant frequency
D. purely resistive circuit
E. None of the above
Answer» C. parallel RLC circuit operated above its resonant frequency
Discussion
3967.

Doubling the operating frequency of an inductive circuit:

A. has no effect on the inductive reactance
B. doubles the amount of inductive reactance
C. multiplies the inductive reactance by 6.28
D. cuts the inductive reactance in half
E. None of the above
Answer» C. multiplies the inductive reactance by 6.28
Discussion
3968.

A circuit has a Norton current of 10 mA and a Norton resistance of 10 kW. What is the Thevenin circuit?

A. 1000 V and a series resistance of 10 k Ohm
B. 100 V and a parallel resistance of 10 k Ohm
C. 100 V and a series resistance of 10 k Ohm
D. 1000 V and a parallel resistance of 10 kOhm
E. None of the above
Answer» D. 1000 V and a parallel resistance of 10 kOhm
Discussion
3969.

A power transformer steps 100 V down to 10 V. If the current in its primary winding is 2 A, what is the current in the secondary winding?

A. 50 A
B. 12 A
C. 5 A
D. 20 A
E. None of the above
Answer» E. None of the above
Discussion
3970.

Assuming 100% efficiency, what is the power being applied to the primary winding of the transformer described in the above question?

A. 200 W
B. 1000 W
C. 20 W
D. 100 W
E. None of the above
Answer» B. 1000 W
Discussion
3971.

To get the Thevenin voltage, you have to

A. Short the load resistor
B. Open the load resister
C. Short the voltage source
D. Open the voltage source
E. None of the above
Answer» B. Open the load resister
Discussion
3972.

Which one of the following properties of a magnetic circuit can be directly compared to resistance in an electrical circuit?

A. Reluctance
B. Permeability
C. Permeance
D. Retentivity
E. There is no valid comparison
Answer» B. Permeability
Discussion
3973.

How many types of flow are there in a semiconductor?

A. 0
B. 1
C. 2
D. 4
E. None of the above
Answer» D. 4
Discussion
3974.

What is the impedance of a circuit composed of a 100 ohm resistor connected in parallel with a capacitor that has a reactance of 100 ohm?

A. 60 Ohm
B. 99.3 Ohm
C. 250 Ohm
D. 70.7Ohm
E. None of the above
Answer» E. None of the above
Discussion
3975.

Current can flow through a normally open push button switch as long as:

A. you are pressing the button
B. you are not pressing the button
C. its contact remain open
D. its contact remain open
E. None of the above
Answer» C. its contact remain open
Discussion
3976.

Doubling the operating frequency of a purely capacitive circuit:

A. has no effect on the total circuit current
B. doubles the amount of total current
C. cuts the total current by one-half
D. thrice the amount of total current
E. None of the above
Answer» C. cuts the total current by one-half
Discussion
3977.

How much current flows through a 0.02 micro F capacitor that is operating from a 12-V ac, 100-Hz source?

A. 0.151 mA
B. 157 raA
C. 0.995 mA
D. 2.02 A
E. None of the above
Answer» B. 157 raA
Discussion
3978.

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

A. The impedance is greater than the sum of the resistance and capacitive reactance
B. The impedance is equal to the sum of the resistance and capacitive reactance
C. The impedance is greater than either the resistance or capacitive reactance but less than their sum
D. The impedance is less than the sum of the resistance and capacitive reactance
E. None of the above
Answer» D. The impedance is less than the sum of the resistance and capacitive reactance
Discussion
3979.

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

A. down
B. up
C. nowhere
D. off the load line
E. None of the above
Answer» C. nowhere
Discussion
3980.

An unloaded zener regulator has a source voltage of 20 V, a series resistance of 330 W, and a zener voltage of 12 V, What is the Zener current?

A. 28.4 mA
B. 24.2 mA
C. 34.4 mA
D. 68.4 mA
E. None of the above
Answer» C. 34.4 mA
Discussion
3981.

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?

A. 1/4
B. 1/3
C. 2
D. 3
E. None of the above
Answer» E. None of the above
Discussion
3982.

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

A. 100 Ohm
B. Less than 1 Ohm
C. 628 Ohm
D. 444 Ohm
E. None of the above
Answer» D. 444 Ohm
Discussion
3983.

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

A. The total voltage in a parallel circuit is less than the value of the smallest voltage
B. The algebraic sum of voltages in a loop is equal to zero
C. The voltage drop across a resistance is proportional to the value of resistance and the amount of current flowing through it
D. The algebraic sum of voltages entering and leaving a point is equal to zero
E. None of the above
Answer» C. The voltage drop across a resistance is proportional to the value of resistance and the amount of current flowing through it
Discussion
3984.

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

A. Current and voltages are in phase through a resistor
B. Current leads the voltage through a resistor
C. Current lags the voltage through a resistor
D. All of the above
E. None of the above
Answer» B. Current leads the voltage through a resistor
Discussion
3985.

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

A. Inductive reactance is an opposition to current flow in dc circuits
B. Inductive reactance is an opposition to current flow in ac circuits
C. Inductive reactance is another term for counter emf
D. Inductive reactance is a force that tends to overcome the effects of counter emf
E. None of the above
Answer» C. Inductive reactance is another term for counter emf
Discussion
3986.

What is the power dissipation of a resistance that has 24 V dropped across it and 0.25 A flowing through it?

A. 3 W
B. 6 W
C. 64 W
D. 122 W
E. None of the above
Answer» C. 64 W
Discussion
3987.

What are the main parts of an atom?

A. Protons only
B. Electrons, protons, and ions
C. Electrons, ions, and neutrons
D. Electrons, protons, and neutrons
E. None of the above
Answer» E. None of the above
Discussion
3988.

Current is

A. The flow of charged particles through a material
B. An imbalance of electrical charges
C. The force that causes electrons to flow
D. The number of free electrons in an atom
E. None of the above
Answer» B. An imbalance of electrical charges
Discussion
3989.

Which one of the following statements is true for voltage in a parallel circuit?

A. The total voltage in a parallel circuit is equal to the average value of the individual voltages
B. The total voltage in a parallel circuit is always less than the value of the smallest voltage
C. The total voltage is equal to the sum of the voltages across the individual branches in a parallel circuit
D. The total voltage of a parallel circuit is the same as the voltages across each branch
E. None of the above
Answer» E. None of the above
Discussion
3990.

Which one of the following statements applies to common auto batteries?

A. Auto batteries are primary wet-cell batteries
B. Auto batteries are secondary wet-cell batteries
C. Auto batteries are secondary dry-cell batteries
D. Auto batteries are primary dry-cell batteries
E. None of the above
Answer» C. Auto batteries are secondary dry-cell batteries
Discussion
3991.

Determine the resistance value and tolerance of a resistor that has the following color bands; first band is red, second band is red, third band is orange, and the fourth band is gold

A. 220 Ohm, 5%
B. 220 Ohm, 10%
C. 22,000 Ohm, 5%
D. 22, 000 Ohm, 10%
E. None of the above
Answer» D. 22, 000 Ohm, 10%
Discussion
3992.

Which one of the following is most likely used for measuring the rate of electron flow?

A. Voltmeter
B. Ammeter
C. Wattmeter
D. Ohmmeter
E. None of the above
Answer» C. Wattmeter
Discussion
3993.

Which one of the following kinds of materials has the highest permeability?

A. A diamagnetic material
B. A ferromagnetic material
C. A paramagnetic material
D. All of the above
E. None of the above
Answer» C. A paramagnetic material
Discussion
3994.

What is the inductive reactance of a 2-H coil operating at 60 Hz?

A. 754 Ohm
B. 30 Ohm
C. 60 Ohm
D. 120 Ohm
E. None of the above
Answer» B. 30 Ohm
Discussion
3995.

Inductive reactance is measured in units of:

A. volts per second
B. amperes per second
C. Ohm
D. henrys
E. None of the above
Answer» D. henrys
Discussion
3996.

What is the difference between the kinds of charges for an electron and a proton?

A. An electron has a positive charge and a proton has no charge
B. An electron has a positive charge and a proton has a negative charge
C. An electron has a negative charge and a proton has a positive charge
D. An electron has a negative charge and a proton has no charge
E. None of the above
Answer» D. An electron has a negative charge and a proton has no charge
Discussion
3997.

An ideal voltage source has

A. Zero internal resistance
B. Infinite internal resistance
C. A load dependent voltage
D. A load-dependent current
E. None of the above
Answer» B. Infinite internal resistance
Discussion
3998.

The dielectric constant of a material is a measure of:

A. the amount of voltage it can withstand before breaking down
B. how well the material concentrates electrostatic lines of force
C. the amount of opposition to the current flow
D. how well the material concentrates magnetic lines of force
E. None of the above
Answer» C. the amount of opposition to the current flow
Discussion
3999.

What is the primary difference between primary and secondary cell batteries?

A. Primary-cell batteries can be recharged and used many times, whereas secondary-cell batteries cannot be properly recharged
B. Secondary-cell batteries can be recharged and used many times, whereas primary-cell batteries cannot be properly recharged
C. Primary-cell batteries use chemical cells, whereas secondary-cell batteries use an alternative energy source, such as thermal or magnetic energy, to supplement their outputs
D. Primary-cell batteries must be recharged at a much slower rate that secondary-cell batteries
E. None of the above
Answer» C. Primary-cell batteries use chemical cells, whereas secondary-cell batteries use an alternative energy source, such as thermal or magnetic energy, to supplement their outputs
Discussion
4000.

When operating below its resonant frequency, a series RLC circuit has the characteristics of a:

A. series RL circuit
B. series RC circuit
C. series RLC circuit operated above its resonant frequency
D. purely resistive circuit
E. None of the above
Answer» C. series RLC circuit operated above its resonant frequency
Discussion