Transcript ElectricCurrentMCquestions

1.
In the circuit below, which meter is not correctly connected?
1
A
3
V
2
A
4
V
A.
B.
C.
D.
1
2
3
4
2.
In the circuit below, n charge carriers pass the point
P in a time t. Each charge carrier has charge q.
P
The current in the circuit is given by the expression
A.
q
t
.
B.
nq
t
.
C.
.
qt
n
D.
nqt.
3.
The graph below shows the variation with voltage V of the
current I in three resistors X, Y and Z.
• Which of the following
corresponds to
resistors for which the
resistance increases
with increasing
current?
• A. X only
• B. Z only
• C. X and Z
• D. Y and Z
I
X
Y
Z
0
0
V
4.The diagrams below show combinations X, Y and Z of
three resistors, each resistor having the same resistance.
•
Which one of the following shows the
resistances of the combinations in
increasing order of magnitude?
com bination X
com bination Y
com bination Z
lowest
®
highest
A.
Y
X
Z
B.
Z
X
Y
C.
X
Y
Z
D.
Z
Y
X
5.
The element of an electric heater has a resistance R
when in operation. What is the resistance of a second
heater that has a power output three times as large at the
same operating voltage?
A.
B.
C.
R
R
9
3
3R
D.
9R
6.
The graph below shows the current/voltage
characteristics of a filament lamp.
24
16
–3
C urrent / × 10 A
8
0
0
2
4
6
Voltage / V
8
• The
resistance of
the filament
at 4.0 V is
• A. 250 Ω.
10
• B. 4 000 Ω.
• C. 8 000 Ω.
• D. 64 000 Ω.
7.
The variation with potential difference V of the
current I in an electric lamp is shown below
• At point P, the current is
Ip, the potential difference
is Vp and the gradient of
the tangent to the curve is
G. What is the resistance
of the lamp at point P?
I
P
Ip
0
0
A.
Vp
1
G
B.
V
G
C.
Ip
Vp
D.
Vp
Ip
8.
Which one of the following shows a correct circuit,
using ideal voltmeters and ammeters, for measuring the I-V
characteristic of a filament lamp?
A.
B.
A
A
V
C.
V
D.
A
A
V
V
9.
A cell of e.m.f. E and internal resistance r is connected to a
variable resistor. A voltmeter is connected so as to measure the
potential difference across the terminals of the cell. Which one of the
following is the correct circuit diagram of the arrangement?
A.
B.
E
r
E
r
V
V
C.
r
E
V
D.
r
E
V
10.
A battery is connected in series with a resistor R.
The battery transfers 2 000 C of charge completely round
the circuit. During this process, 2 500 J of energy is
dissipated in the resistor R and 1 500 J is expended in the
battery.
•
•
•
•
•
The e.m.f. of the battery is
A. 2.00 V.
B. 1.25 V.
C. 0.75 V.
D. 0.50 V.
11.
The current in the circuit shown below is constant
when the switch is closed.
• The energy transfer in the internal
resistance r of the battery is 15 J
when a charge of 40 C passes
through it. For the same amount
of charge, 45 J of energy is
transferred in the resistor R.
•
Which of the following gives
the e.m.f. of the battery?
r
R
A.
B.
C.
15
40
V
30
40
45
V
40
D.
V
60
40
V
12.
In the circuits below, the cells each have the same
e.m.f. and zero internal resistance. All the resistors have
the same resistance.
C ircuit X
C ircuit Y
C ircuit Z
• Which of the following gives the current through
the cells in order of increasing magnitude?
Lowest current
®
Highest current
A.
X
Y
Z
B.
Z
X
Y
C.
Y
Z
X
D.
Y
X
Z
13.
The graph shows the variation with applied potential
difference V of the current I in an electrical component.
• Which one of
the following
gives the
resistance of
the component
at point P?
I
I1
P
A.
0
0
B.
C.
The gradient of the line at P
v
V1
The reciprocal of the gradient of the line at P
The ratio
I1
V1
D.
The ratio
V1
I1