Download There are 9 Multiple choice questions, 3 fill in the blank, and two

6. The watt-hour is a unit of
IUS - FENS - EE - Fall 2014
ENS203 Electrical Circuits Quiz 2 (27.Oct.2014)
Time allowed - 15 minuets (extra 10 minutes for coming
early)
Name:
ID:
(A)
(a)
(b)
(c)
(d)
There are 9 Multiple choice questions, 3 ll in
the blank, and two essay problems
7. According to Ohm's law, which of the following is
directly proportional to voltage if resistance is kept
constant?
1. If a variable voltage source is set to 12 volts, to what
voltage must it be adjusted to decrease the circuit's
current by 25%
(a)
(b)
(c)
(d)
(a)
(b)
(c)
(d)
Increase it to 16 V
Increase it to 20 V
Decrease it to 9 V
Decrease it to 6 V
Current
Frequency
Reactance
Electromotive force
8. Practical systems have an eciency
2. A certain resistor with color code of
(Red/Red/Red/Gold). If the resistor was connected across the terminals of 12 volts battery, The
nominal current owing through the resistor is:
(a)
(b)
(c)
(d)
energy
power
eciency
amount of money
(a)
(b)
(c)
(d)
5.19 mA
5.45 mA
5.74 mA
6.0 mA
positive and equal to100% z
negative and less than 100%
positive and less than 100%
positive and more than 100%
9. With no external forces applied, the net ow of charge
in a conductor in any one direction is
(a)
(b)
(c)
(d)
3. Which one of these statements is true of the ohmmeter?
negative
positive
maximum
zero
(a) It is used to measure resistance of a single resistor in a network without removing the resistor
II Fill in the blanks
from the circuit
(b) It is used to measure resistance in a circuit on;y
1. A solar cell with an eciency of 12% drives a small
of the circuit is powered by low-voltage batteries
motor of an eciency of 85%. The total eciency is:
...............................
(c) It should be stored with the selector switch in
the resistance mode
2. One kilowatt-hour is equivalent to ..........................
(d) It displays a resistance of zero if the leads touch
joules
each other, and an innite reading if there is no
3. The
power
dissipated
by
a
resistor
connection at all.
......................................
if the applied voltage
4. If an electrical circuit draws 1A at 50V, how much
doubles. (how much the decrease or the increase)
current will it draw if the voltage is increased to 75
V?
III What is the name of the author of our text
(a)
(b)
(c)
(d)
book?
1.5 A
15 mA
IV For the circuit shown, identify which elements
are giving power and which elements are
absorbing and how much is that power
15µA
1.5
mA
5. A power supply provides a continuous 200 W to a
load, with an eciency of 80%. In 24-hour period
how many KWh of energy does it consume?
(a)
(b)
(c)
(d)
6 KWh
250 KWh
600 KWh
4.8 KWh?
1