200+ câu Trắc nghiệm Tiếng Anh chuyên ngành kỹ thuật điện có đáp án - Phần 4
25 câu hỏi
......... does not readily release electrons
Cooper
Aluminum
Steel
Rubber
Chọn đáp án D
Other devices such as capacitors and ......... may also be located at a substation
cooling tower
governer
current regulators
voltage regulators
Chọn đáp án D
An overhead power line consists of one or more conductors suspended by ....... or poles.
isolators
capacitors
resistors
towers (cột điện)
Chọn đáp án D
In switching substation, there is not any .......
insulator
isolator
circuit breaker
transfomer
Chọn đáp án D
Residential customers are supplied with .......... levels of 220/380 V
potential
electromotive force
current
voltage
Chọn đáp án D
A resistance of 5k ohm has a conductance of? G= 1/R = 1/(5.10³) =0,2x10⁻³s=0.2 ms
2S
0.2kS
0.2mS
2mS
Chọn đáp án C
The electric power which ...... is stepped up to a higher voltage at which it connects to the transmission grid.
are generating
generates
is generated
transformer
Chọn đáp án C
An electric grid or power grid is an interconnected network for ........ electricity from producers to consumers.
generating
changing
delivering
consuming
Chọn đáp án C
A coil which has a resistance of 2Ω is connected to a 20V DC supply. Which is the value of current?
1A
10A
0,1A
100A
Chọn đáp án B
In power system, which of following statements is correct ?
The device which takes electrical energy is known as the electric load
The source which generate electrical energy is known as the electric load
a dam is considered as a load
a transformer being separed from the power network is considered as a load
Chọn đáp án A
A distribution substation(trạm biến áp phân phối) .......... voltage to a value suitable for local loads.
supports
increases
remains
reduces
Chọn đáp án D
Voltis the unit of
Electric Circuit
Electric Current
Potential Difference
Volt-meter
Chọn đáp án C
For any node in ............, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node; or equivalently:
Counter
Electric power plante
An winding
An electrical circuit
Chọn đáp án D
The power factor is a ratio of ……...
Real power to reactive power
Real power to apparent power
Reactive power to apparent power
Reactive power to real power
Chọn đáp án B
Write out P = VIcos in full
The active power equals the product of the voltage, the current, and power factor.
P equals to the product of V, I, and cos.
P equals the product of V, I, and cos.
P equals the product of V, I, c, o, s, and .
Chọn đáp án S
Filaments of electric bulbs are usually made of ………….
Nichrome
Tungsten
Copper
Carbon
Chọn đáp án B
Write out P = VIcos in full
The active power equals the product of the voltage, the current, and power factor.
P equals to the product of V, I, and cos.
P equals the product of V, I, and cos.
P equals the product of V, I, c, o, s, and .
Chọn đáp án A
Write out V 2 + V 3 = V 1 in full
Voltage two plus Voltage three is equal to Voltage three
V one equals V two plus V three
V two plus V three is equal to V one
V two plus V three equal to V one
Chọn đáp án C
An electric current running through a wire produces ... around the wire
an electromanet
a current
a magnetic field (từ trường)
an electric field
Chọn đáp án C
In the alternative current circuit, which of following statements is correct?
The voltage across a capacitor leads the current by 90°.
The voltage across a capacitor lags the current by 90
The voltage across a capacitor in phase the current
All 3 statement above are true.
Chọn đáp án B
A circuit contains two un-equal resistances in parallel
smaller resistance has smaller conductance
potential difference across each is same
large current flows in larger resistor
current is same in both
Chọn đáp án B
A source e.m.f of 5V provides a current of 5A for 1minute. How much energy is provided in this time? (E=VIT=5.5.60=1500(J)=1.5(KJ)).
250J
150J
1.5kJ
25J
Chọn đáp án C
“I one plus I two equals four fifths of I three” is the full expression of
I1+I2=I3
I1+I2=I3
I1+I2=I3
I3=I1+I2
Chọn đáp án D
........ feeds power from one point to another without being tapped from any intermediate point.
Transformer
Circuit breaker
Generator
Feeder
Chọn đáp án D
Which devices are used to interurpt short-circuit currents in the power system?
Current transformers
Voltage transformers
Isolators
Circuit breakers
Chọn đáp án D
