通信专业英语之交流电、直流电以及电信号英语拓展

Exercises
5.The effective value of AC is the value of alternating voltage or current that will have the same effect on a resistance as a comparable value of direct voltage or current will have on the same resistance. (T)
5.When reading an oscilloscope trace it is usual to measure peak-peak voltage.
Exercises
ⅠⅠ
Match the following terms to appropriate definition or expression.
Exercises
a.An electrical signal 1./ time period
b.Peak voltage 2.the maximum voltage reached
2.Alternating Current (AC) always flows in the same direction. ge reached by the signal. (F)
4.Peak-peak voltage is twice the peak voltage (amplitude). (T)
Exercises
Ⅰ
Write T(True) or F(false) beside the following statements about the text.
Exercises
1.Direct Current (DC) flows one way, then the other way, continually reversing direction. (F)
Exercises
Ⅲ
Fill in the missing words according to the text.
Exercises
1.An AC voltage is continually changing between positive and negative.
2.Electronic circuits normally require a steady DC supply which is constant at one value.
3.Cells, batteries and regulated power supplies provide steady DC which is ideal for electronic circuits.
Exercises
4.In addition to the properties labeled on the graph, there is frequency which is the number of cycles per second.
by the signal
c.Peak-peak voltage 3.twice the peak voltage
(amplitude)
d.Frequency
4. a voltage or current
which conveys information
The answer:
a-4
b-2 c-3 d-1