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Physics PHY407
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NAME: _________________________________
QUIZ 2 –
Semester Jul08-Nov08
KP UiTM: ________________
Sept 11th 2008
Answer ALL questions ON the question paper itself. DO NOT USE ADDITIONAL
PAPERS.
On this test, all batteries are ideal (they have no internal resistance), and
connecting wires have no resistance. Unlike most real bulbs, the resistances of
the bulbs on this test do not change as the current through them changes.
1.
A bulb and a battery are connected as shown below.
A)
B)
C)
D)
E)
F)
The current is largest at A.
The current is largest at B.
The current is largest at C.
The current is largest at D.
The current is the same everywhere.
The current is the same between A and B and smaller than between C and
D.
G) The current is the same between A and B and larger than between C and D.
H) The current is the same everywhere except in the bulb.
I) The current is the same everywhere except in the battery.
J) None of these is true.
For Questions 2-5, a second identical bulb is added to the circuit in Question 1, as
shown below.
2.
Compare the current at A now to the current at A before when there was only
one bulb.
A) The current at A is now twice as large as before.
B) The current at A is now larger than before but not twice as large.
C) The current at A is the same as before.
D) The current at A is now half as large as before.
E) The current at A is now smaller than before but not half as large.
J) None of these is correct.
3.
Compare the current through the bulb connected between B and C now to the
current through it before when there was only one bulb.
A) The current is larger than it was before.
B) The current is the same as before.
C) The current is smaller than it was before.
Quiz 2
Lecturer: Dr. JJ
06/27/17
Physics PHY407
Page 2 of 3
Semester Jul08-Nov08
4.
Compare the brightness of the bulb connected between B and C now to its
brightness before when there was only one bulb.
A) The bulb is brighter than it was before.
B) The bulb is just as bright as before.
C) The bulb is dimmer than it was before.
5.
Compare the potential difference across the bulb, VBC, with the two bulbs in the
circuit compared to when there was only one bulb.
A) The potential difference is now twice as large as before.
B) The potential difference is now larger than before but not twice as large.
C) The potential difference is the same as before.
D) The potential difference is now half as large as before.
E) The potential difference is now smaller than before but not half as large.
J) None of these is correct.
For questions 6-8, a second identical bulb is added to the circuit in Question 1 as shown
below.
6.
Compare the current at A now to the current at A with only one bulb.
A) The current at A is now twice as large as before.
B) The current at A is now larger than before but not twice as large.
C) The current at A is the same as before.
D) The current at A is now half as large as before.
E) The current at A is now smaller than before but not half as large.
J) None of these is correct.
7.
Compare the potential difference across the bulb, VBC, now to what it was
before when there was only one bulb.
A) The potential difference is now twice as large as before.
B) The potential difference is now larger than before but not twice as large.
C) The potential difference is the same as before.
D) The potential difference is now half as large as before.
E) The potential difference is now smaller than before but not half as large.
J) None of these is correct.
8.
Compare the brightness of the bulb connected between B and C to its
brightness before when there was only one bulb.
A) The bulb is brighter than it was before.
B) The bulb is just as bright as before.
C) The bulb is dimmer than it was before.
9.
Which one of the following situations results in a conventional electric current
that flows westward?
A) A beam of protons moves eastward
B) An electric dipole moves westward
C) A beam of electrons moves westward
D) A beam of electrons moves eastward
E) A beam of neutral atoms moves westward
10.
How many electrons flow through a battery that delivers a current of 3.0 A for 12
s?
A) 4 B) 36 C) 4.8 × 1015 D) 6.4 × 1018 E) 2.2 × 1020
Quiz 2
Lecturer: Dr. JJ
06/27/17
Physics PHY407
Page 3 of 3
Semester Jul08-Nov08
11.
The potential difference across the ends of a wire is doubled in magnitude. If
Ohm’s law is obeyed, which one of the following statements concerning the
resistance of the wire is true?
(a) The resistance is one half of its original value.
(b) The resistance is twice its original value.
(c) The resistance is not changed.
(d) The resistance increases by a factor of four.
(e) The resistance decreases by a factor of four.
12.
Which one of the following statements concerning resistance is true?
A) The resistance of a semiconductor increases with temperature.
B) Resistance is a property of resistors, but not conductors.
C) The resistance of a metal wire changes with temperature.
D) The resistance is the same for all samples of the same material.
E) The resistance of a wire is inversely proportional to the length of the wire.
13.
A 4-A current is maintained in a simple circuit with a total resistance of 2 W. How
much energy is delivered in 3 seconds?
A) 3 J B) 6 J C) 12 J D) 24 J E) 96 J
14.
A 40-W and a 60-W light bulb are designed for use with the same voltage. What is
the ratio of the resistance of the 60-W bulb to the resistance of the 40-W bulb?
A) 1.5 B) 0.67 C) 2.3 D) 0.44 E) 3.0
15.
Two wires, A and B, and a variable resistor, R, are connected in series to a battery.
Which one of the following results will occur if the resistance of R is increased?
A)
The current through A and B will increase.
B)
The voltage across A and B will increase.
C)
The voltage across the entire circuit will increase.
D)
The power used by the entire circuit will increase.
E)
The current through the entire circuit will decrease.
16.
In the circuit configuration below,
i)
ii)
iii)
Label the ‘+’ and ‘-‘ on the batteries and the resistors to show the high and
low potential end.
Apply Kirchoff’s current rule at junction A.
Apply Kirchoff’s voltage rule on loop ABCDA and on loop FADEF
respectively.
F
A
1 = 5 V
4 = 20 V
2 = 10 V
3 = 15 V
R2 = 15 
I1
I2
I3
R3 = 10 
E
B
R1 = 20 
C
D
(6+3+8=17 marks)
Quiz 2
Lecturer: Dr. JJ
06/27/17