# Test For Engineer(Pdb, Desco,Desa)

74 Questions  Settings  Related Topics
• 1.
Resistivity of a wire depends on
• A.

Length

• B.

Material

• C.

Cross section area

• D.

None

• 2.
When n resistances each of value r are connected in parallel, then resultant resistance is x. When these n resistances are connected in series, total resistance is
• A.

Nx

• B.

Mx

• C.

X/n

• D.

N^2 x.

• 3.
Resistance of a wire is r ohms. The wire is stretched to double its length, then its resistance in ohms is
• A.

R/2

• B.

4r

• C.

2r

• D.

R/4

• 4.
Kirchhoff's second law is based on law of conservation of
• A.

Charge

• B.

Energy

• C.

Momentum

• D.

Mass

• 5.
The diameter of the nucleus of an atom is of the order of
• A.

10^ -31 m

• B.

10^ -25 m

• C.

10^ -21 m

• D.

10^ -14 m

• 6.
The mass of proton is roughly how many times the mass of an electron?
• A.

184000

• B.

18400

• C.

1840

• D.

184

• 7.
The charge on an electron is known to be 1.6 x 10-19 coulomb. In a circuit the current flowing is 1 A. How many electrons will be flowing through the circuit in a second?
• A.

1.6 x 10^19

• B.

1.6 x 10^-19

• C.

0.625 x 10^19

• D.

0.625 x 10^12

• 8.
Two bulbs marked 200 watt-250 volts and 100 watt-250 volts are joined in series to 250 volts supply. Power consumed in circuit is
• A.

33 watt

• B.

67 watt

• C.

100 watt

• D.

300 watt

• 9.
Ampere second could be the unit of``
• A.

Power

• B.

Conductance

• C.

Energy

• D.

Charge

• 10.
Which of the following is not the same as watt?
• A.

Joule/sec

• B.

Amperes/volt

• C.

amperes x volts

• D.

( amperes )^2 x ohm.

• 11.
An electric current of 5 A is same as
• A.

5 J / C

• B.

5 V/ C

• C.

5 C/ sec

• D.

5 W / sec

• 12.
An electron of mass m kg and having a charge of e coulombs travels from rest through a potential difference of V volts. Its kinetic energy will be
• A.

EV Joules

• B.

MeV Joules

• C.

Me/V Joules

• D.

V/me Joules

• 13.
A circuit contains two un-equal resistances in parallel
• A.

Current is same in both

• B.

large current flows in larger resistor

• C.

Potential difference across each is same

• D.

Smaller resistance has smaller conductance

• 14.
In an alternator, voltage drops occurs in
• A.

Armature resistance only

• B.

Armature resistance and leakage reactance

• C.

Armature resistance, leakage reactance and armature reaction

• D.

armature resistance, leakage reactance, armature reaction and earth connections.

• 15.
The magnitude of various voltage drops that occur in an alternator, depends on
• A.

• B.

• C.

• D.

• 16.
The total impedance of a parallel LC circuit approaches “x” as the power supply frequency approaches resonance
• A.

Infinity

• B.

Unity

• C.

Lagging

• 17.
When multiple sine waveforms are mixed together (as is often the case in music), the lowest frequency sine-wave is called the fundamental, and the other sine-waves whose frequencies are whole-number multiples of the fundamental wave are called
• A.

Low band width

• B.

Harmonics

• C.

High band width

• 18.
Capacitors store energy in the form of an electric field, and electrically manifest that stored energy as a potential:
• A.

Static voltage

• B.

Capacitive voltage

• C.

Variable voltage

• 19.
When the power supply frequency for an AC circuit exactly matches that circuit’s natural oscillation frequency as set by the L and C components, a condition of “x” will have been reached.
• A.

Resonance

• B.

Reactance

• C.

Impedance matching

• 20.
A capacitor and inductor directly connected together form something called a “x” circuit,
• A.

Tank

• B.

Capacitive

• C.

Inductive

• 21.
Resistance is essentially “x” against the motion of electrons.
• A.

Inertia

• B.

Friction

• C.

Impact

• 22.
Reactance is essentially “x” against the motion of electrons.
• A.

Friction

• B.

Inertia

• C.

Impact

• 23.
Inductive reactance increases with increasing
• A.

Frequency

• B.

Current

• C.

Power factor

• 24.
A purely resistive impedance will always have a phase angle of exactly
• A.

0 degree

• B.

90 degree

• C.

360 degree

• 25.
The “x” effect is where alternating current tends to avoid travel through the center of a solid conductor, limiting itself to conduction near the surface.
• A.

Ferrari

• B.

Skin

• C.

Capacitive

• 26.
The equation for approximating skin effect at high frequencies (greater than 1 MHz) is : RAC = (RDC)(k) root of F. what k means here?
• A.

Wire gauge factor

• B.

Wire resistance factor

• C.

Co. efficient temperature of resistance

• 27.
A “x” number is a mathematical quantity representing two dimensions of magnitude and direction.
• A.

Scalar

• B.

Vector

• C.

Complex

• 28.
All the laws and rules of DC circuits apply to AC circuits, with the exception of “x” calculations
• A.

Power

• B.

Voltage

• C.

Current

• 29.
A changing electric field produces a perpendicular “x” field,
• A.

Magnetic

• B.

Electric

• C.

Current

• 30.
A changing magnetic field produces a perpendicular “x” field.
• A.

Magnetic

• B.

Electric

• C.

Current

• 31.
Analog, electromechanical meter movements respond proportionally to the “x” of an AC voltage or current.
• A.

Rms value

• B.

Average value

• C.

Peak value

• 32.
A “x” waveform is defined as one waveform that is ahead of another in its evolution.
• A.

Lagging

• B.

• C.

Unity

• 33.
The “x” of an AC waveform is the ratio of its RMS value to its average value.
• A.

Form factor

• B.

Crest factor

• C.

Rms factor

• 34.
Frequency is described as 1/”x”. What x means here?
• A.

Period

• B.

Magnitude

• C.

Amplitude

• 35.
The “x” of a wave is the amount of time it takes to complete one cycle. What x means here?
• A.

Period

• B.

Magnitude

• C.

Amplitude

• 36.
“x” is a way of expressing an AC quantity of voltage r current in terms functionally equivalent to DC.
• A.

Rms

• B.

Average

• C.

Peak value

• 37.
The “x” of an AC waveform is its height as depicted on a graph over time
• A.

Period

• B.

Magnitude

• C.

Amplitude

• 38.
• A.

Short circuit

• B.

Earthing

• C.

Lighting arrester

• 39.
• A.

Neutral supply

• B.

Earthing

• C.

Antenna

• 40.
• A.

Outgoing feeder

• B.

Current flow

• C.

Incoming feeder

• 41.
• A.

Outgoing feeder

• B.

Current flow

• C.

Incoming feeder

• 42.
• A.

Meter box

• B.

Inverter

• C.

Rectifier

• 43.
• A.

meter box

• B.

Inverter

• C.

Rectifier

• 44.
• A.

Current transformer

• B.

Auto transformer

• C.

Voltage transformer

• 45.
• A.

Current transformer

• B.

Auto transformer

• C.

Voltage transformer

• 46.
• A.

Inertia switch

• B.

Two way switch

• C.

Spark plug

• 47.
• A.

Capacitor

• B.

clutch break

• C.

Isolator

• 48.
• A.

Or gate

• B.

Nor gate

• C.

Nand gate

• 49.
PIM stands for?
• 50.
• A.

1 phase line

• B.

Line damaged

• C.

Line open

• 51.
Find out what it means?
• A.

3phase delta winding

• B.

3 phase cable

• C.

3 phase star winding

• 52.
What is the unit of resistance?
• A.

Ohm

• B.

Volt

• C.

Amp

• D.

• E.

Henry

• 53.
How does hydrpelectric energy work?
• A.

It uses the power of the sun to turn work

• B.

Water turns a piece similar to a propeller to power

• C.

The water heats up and it turns into water vaper to power

• D.

Water freezes and then is thrown to power it

• 54.
• A.

Its renewable

• B.

Low maintennce costs

• C.

Its costs very little to make

• D.

Fuel is not burned

• 55.
True or false? is hydroelectric energy a nonreneable resource?
• A.

True

• B.

False

• 56.
Where is hydroelectric energy used the most
• A.

United states

• B.

Japan

• C.

Geenland

• D.

China

• 57.
What pulls water into the penstock?
• A.

Gravity

• B.

The force of all the water

• C.

Gary falkman

• D.

The turbine

• 58.
Why is it so easy for hydroelectric energy to make energry
• A.

• B.

Water is everywhere so you can use it everywhere

• C.

It dosent cost that much to make one

• D.

It rains all the time

• 59.
What is a main power plant for hydroelectric energy
• A.

Rivers

• B.

Oceans

• C.

Dams

• D.

Sunflowers

• 60.
Blank is in a dam that is powering and making the energy
• A.

Tubines

• B.

Water

• C.

Justin beaber

• D.

Gravity

• 61.
Hydroelectric energy converts gravitational potential energyof water into
• A.

Power

• B.

Kinetic energy

• C.

Kittens

• D.

Mechnical energy

• 62.
Circuit breaker
• A.

The rate at which electrical energy is converted to another form of energy,

• B.

Device that prevents a circuit from overheating and causing a fire.

• C.

Devices that use electrical energy.

• D.

Metal that melts if the current becomes too high.

• 63.
T  or   FTo use electrical energy, a complete circuit must be made.
• A.

True

• B.

False

• 64.
The circuit has only one loop to flow through.
• A.

Series

• B.

Closed

• C.

Parallel

• D.

Open

• E.

Fused

• 65.
T  or FWhen any part of a series circuit is discontinued, most of the currency flows through the circuit.
• A.

True

• B.

False

• 66.
T  or FOpen circuit is the same as series circuit because the parts of a series circuit are wired one after another thus the amount of current is the same through every part.
• A.

True

• B.

False

• 67.
Contains two or more branches for current to flow through.
• A.

Series

• B.

Open

• C.

Parallel

• D.

Fuses

• 68.
T  or FAccording to Ohms Law, more currents flow through the branches that have higher resistance.
• A.

True

• B.

False

• 69.
Contains a small piece of metal that melts if the current becomes too high.
• A.

Series

• B.

Open

• C.

Parallel

• D.

Fuses

• 70.
T  or FMelting of a fuse causes a break in the circuit, stopping the flow of current through the over circuit.
• A.

True

• B.

False

• 71.
A change in composition or structure is called ____.
• A.

Energy

• B.

Transformation

• C.

Generator

• D.

Turbine

• E.

Reformation

• 72.
Energy forms can be ____.
• A.

Chemical

• B.

Thermal

• C.

Electrical

• D.

• E.

All of the above

• 73.
Where is the potential energy greatest?
• A.

At the dip two cars past the red arrow.

• B.

As the car is moving up the hill 3 cars past the red arrow.

• C.

At the top of the hill before the red arrow.

• D.

There is no example of potential energy.

• 74.
Where is the kinetic energy GREATEST?
• A.

As the biker is climbing the hill.

• B.

As the biker is at the top of the hill.

• C.

AS the biker is on the downside of the hill.

• D.

There is no example of kinetic energy.