Chapter 21:
Electric Fields
Practice Test
1.
The ratio of charge stored to electric potential difference is called the __________.
a.
capacitor
b.
capacitance
c.
current
d.
resistance
Hint
2.
An electric field is to be measured using a positive test charge of 3.0 × 10
-5
C. This test charge experiences a force of 0.50 N acting at an angle of 15 degrees. What is the magnitude of the electric field at the location of the test charge?
a.
1.7 × 10
3
N/C
b.
1.7 × 10
4
N/C
c.
6.0 × 10
-5
N/C
d.
0.49 N/C
Hint
3.
A voltmeter reads 450 V across two charged, parallel plates that are 5.0 cm apart. What is the electric field between them?
a.
9.0 × 10
3
N/C
b.
1.1 × 10
-4
N/C
c.
9.0 × 10
1
N/C
d.
9.0 × 10
2
N/C
Hint
4.
Two parallel plates are given opposite charges. A voltmeter measures the electric potential difference to be 47.0 V. The plates are 5.0 cm apart. What is the magnitude of the electric field between them?
a.
9.4 × 10
3
N/C
b.
1.1 × 10
-3
N/C
c.
9.4 × 10
2
N/C
d.
1.1 × 10
-4
N/C
Hint
5.
As a positive test charge moves farther from a positive charge in an electric field, the potential energy __________.
a.
remains the same
b.
decreases
c.
doubles
d.
increases
Hint
6.
What work is done when 3.5 C is moved through an electric potential difference of 4.5 V?
a.
1.6 × 10
1
J/C
b.
negative 1.6 × 10
1
J
c.
1.6 × 10
1
J
d.
7.8 × 10
-1
J
Hint
7.
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.
7.7 × 10
5
C
b.
4.5 × 10
-5
C
c.
4.5 × 10
5
C
d.
7.7 × 10
-5
C
Hint
8.
When the electric potential difference between two positions in an electric field is zero, the positions are __________.
a.
close together
b.
at equipotential
c.
in equilibrium
d.
polar
Hint
9.
Electric potential difference is measured in __________.
a.
newtons per coulomb
b.
joules per coulomb
c.
coulombs per joule
d.
volts per coulomb
Hint
10.
An electric field is about 150 N/C downward. What is the direction of the force on a positively-charged particle?
a.
upward
b.
stationary
c.
changes rapidly
d.
downward
Hint
