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ELTECH 113 Lecture (Quiz #5, In-Class)
Date : Thursday (9-26-2002, 5 :30 pm)
Instructor : Bret Allen
Instructions : Select the best possible answer to each of the following (22)
multiple-choice questions :
1.
Current that flows in one direction only is called :
a . alternating current
direct current
c. pulsating ac
d . pulsating do
2.
Alternating current :
a . flows in one direction only
flows in one direction and then in the opposite direction
. flows only from negative to positive
d . flows only from positive to negative
3.
If current rises from zero to a positive point, returns to zero, and
then repeats, it is considered :
a . alternating current
b . a battery charger
c . laser
direct current
4.
If the polarity of ac voltage continually reverses, then so will the :
a . power
b . magnitude
current
d . information
5.
A transformer is used to convert :
ac to ac
b . ac to do
c . do to ac
d . do to do
6.
The power distribution from the power plant to your home is :
a . low voltage to low voltage
b . low voltage to high voltage
high voltage to low voltage
d . high voltage to high voltage
0
ELTECH 113 Lecture (Quiz #5, 22 Multiple-Choice Questions)
Page 2
7 .
What kind of waveform does a simple ac generator produce?
a . pulse wave
sine wave
. square wave
d . triangle wave
8.
If
30
a.
b.
c.
->®
9.
10 .
11 .
the hypotenuse of a right triangle is 60 cm, and one of its sides is
cm, how long is the other side?
5 .15 cm
a-(3o)7
4, a
30 cm
13
45 cm
52 cm
J(6°)
3v
When the right triangle hypotenuse is 25 cm, with an opposite side of 14
cm, what is the value of the angle theta?
SoN CAN ToA
a . .01 degrees
b . 29 degrees
_
-_a5'
34 degrees
d . 56 degrees
=> -e- =
If its sine value is 0 .2, what is the value of the angle theta?
a . 78 .46 degrees
b . 11 .3 degrees
. 0 .2 degrees
~5~
11 .5 degrees
5-7=
= o, a
ssA/
ILI,
What is the value of the angle theta when a right triangle hypotenuse is
10 cm, and its adjacent side is 4 cm?
50H CAIN 7 Al
a . 0 .4 degrees
b . 6 .98 degrees
. 21 .8 degrees
K
66 .4 degrees
10
-Ze?-- -
1
14
12 .
When a
60 cm,
33 .7
b . 41 .8
c . 48 .2
d . 56 .3
right triangle's opposite side is 40 cm and its adjacent side is
what is the value of theta?
S o H CA H T6A
degrees
rr
degrees
degrees h/ O
6J
degrees
13 .
What is the peak value of a household appliance that uses a 230 V ac
source?
6IVEnl ,
Q 3aV
a . 163 V
b . 230 V
_
325 V
l in~D
V
P EAK
V
.480
30V -3-:2 ~~
/6a)
Go
Vn~ -
-
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ELTECH 113 Lecture
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22 Multiple-Choice Questions)
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Page 3
14 .
If an ammeter measures 20 mA of current, what is the peak-to-peak
current
nt
~ value? G1-vc
c~0 /yt f~
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b . 2 8 mA
~1-NO
c . 40 mA
a7 C a~~ N~ r9 '`'
--,"O®5 7 mA
M
3
S V L ~/ ,'
,_ q7
'ale
,~
15 .
16 .
17 .
7o 7
'7 '7
lM A.
the average value of a 12 V peak wave?
--V
^'
1 tJC~V
V
V FrN
76
Vf1 Uc /
V
37 ~cAl~
5 oL nl . V vAF_
If a voltmeter measures a sine wave peak as 500 mV, what would be its
average
L., ,EIV ,' t~FAK - Jr'Oc7 /n V
a . 159 .0 mVue?
318 .5 mV
FZN
D.'
VR vE
c . 353 .5 my
.
-..
d . 451 .0
63
What is
a . 3 .82
b . 4 .24
7 . 64
d . 9 .42
When converted to peak-to-peak, what is the value of a sine wave's
average voltage of 30 volts?
a . 47 v
VAvc ; 3o Il
b . 60 v
-j4:~) 94 V
07 3J1/~
d . 120 v
P -~
yAt/6j, 6 37
L 37
V/0 -~
50
18 . What is the waveform period of the
Hz electricity used in Europe?
0 ms
5 /ScC .
5o f4 -z = ~o C Yc
->~ 50 ms
c. 20 s
^ . O C? ,5r~ =d . 50 s
M S
C,'O h~
vLA .'
~ff
19 . What is the frequency of a sine wave that has a period time of 1 ~xs?
a . 1 MHz
GI (1~1J .~ /~= 1
S = / ClC~ -~' ~ CG. .
b . 1 Hz
~_
c . 1 kHz
-1 MHz
/
/K
O t
_
/7/
= a
7
s
Electrical power in the United States is generated at which frequency?
a . 50 Hz
~.
l
60 Hz
120 Hz
d . 240 Hz
0.5 .
ELTECH 113 Lecture (Quiz #5, 22 Multiple-Choice Questions)
V
Page 4
21 .
22 .
If a sine wave has a waveform period of 30 milliseconds,
frequency?
GT
lam _ 3v ~
a . 21 .21 Hz
33 .33 Hz
0 .03 ms
d . 23 .56 ms
5oL.~,l .~
5 = 3v~ia>_ 3 SEC,
vc,~l .'
Which is the symbol for ac voltage?
a. I
II
III
d . IV
II.
III .
I.
what is its
IV .
7
. C .
ELTECH 113 Lecture
-END OF QUIZ-
(Quiz #5,
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22 Multiple-Choice Questions)
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