Chapter 21:
Electric Fields
Practice Test
1.
Electric potential difference is measured in __________.
a.
volts per coulomb
b.
newtons per coulomb
c.
joules per coulomb
d.
coulombs per joule
Hint
2.
The direction of the electric field is the direction of the__________.
a.
potential difference
b.
force on the negative test charge
c.
force on the positive test charge
d.
work done moving the test charge
Hint
3.
A negative charge of 1.5 × 10
-7
C experiences a force of 0.030 N to the right in an electric field. What is the magnitude and direction of the field?
a.
2.0 × 10
5
N/C directed to the left
b.
4.5 X10
-9
N/C directed to the left
c.
4.5 × 10
-7
N/C directed to the right
d.
2.0 × 10
5
N/C directed to the right
Hint
4.
An electric field is about 150 N/C downward. What is the direction of the force on a positively-charged particle?
a.
upward
b.
downward
c.
changes rapidly
d.
stationary
Hint
5.
The electric field at the location of
q'
is represented by which of the following equations?
a.
E= W/
q'
b.
E= q'/F
q'
c.
E= F/
q'
d.
E= q/ΔV
Hint
6.
A 6.4-ΜF capacitor is first charged so that the electric potential difference is 5.0 V. How much additional charge is needed to increase the electric potential difference to 12.0 V?
a.
4.5 × 10
5
C
b.
7.7 × 10
-5
C
c.
4.5 × 10
-5
C
d.
7.7 × 10
5
C
Hint
7.
A voltmeter reads 450 V across two charged, parallel plates that are 5.0 cm apart. What is the electric field between them?
a.
1.1 × 10
-4
N/C
b.
9.0 × 10
3
N/C
c.
9.0 × 10
1
N/C
d.
9.0 × 10
2
N/C
Hint
8.
A positive test charge of 9.0 × 10
-5
C is in an electric field that exerts a force of 3.7 × 10
-5
N on it. What is the magnitude of the electric field at the location of the test charge?
a.
2.4 N/C
b.
0.41 N/C
c.
4.1 N/C
d.
0.24 N/C
Hint
9.
In a Millikan oil drop experiment, a drop has been found to weigh 1.92 × 10
-14
N. When the electric field is 3.0 × 10
4
N/C, the drop is suspended motionless. What is the charge on the oil drop?
a.
5.8 × 10
-10
C
b.
6.4 × 10
19
C
c.
5.8 × 10
-19
C
d.
6.4 × 10
-19
C
Hint
10.
The SI derived unit of potential difference is the __________.
a.
ohm
b.
volt
c.
coulomb
d.
joule
Hint
