The Atom
Practice Test
1.
What electric potential difference is applied to two metal plates 0.350 m apart if the electric field between them is 3.75×10
3
N/C?
a.
1.07×10
3
V
b.
1.07×10
4
V
c.
1.31×10
3
V
d.
1.31×10
0
V
Hint
2.
What occurs in a material that has the property of piezoelectricity?
a.
It amplifies sound waves.
b.
It bends or deforms when a voltage is applied across it.
c.
It emits infrared radiation.
d.
It produces a beam of light when it enters a magnetic field.
Hint
3.
If Thomson's experiment depicted in Figure 26-1 were done with a proton, how would the magnitude of the
q/m
ratio obtained compare with that for an electron?
a.
It would be the same.
b.
It would be less.
c.
It would be more.
d.
It would depend on the velocity of the proton.
Hint
4.
According to Figure 27-6, what is the approximate frequency needed to eject an electron with a minimum kinetic energy of 2 eV?
a.
8.1×10
14
Hz
b.
10×10
14
Hz
c.
9.2×10
14
Hz
d.
4.5×10
14
Hz
Hint
5.
In the situation depicted in Figure 27-12, if the electron's initial speed is doubled, what stopping potential would be required?
a.
2.5 V
b.
10.0 V
c.
20.0 V
d.
5.0 V
Hint
6.
Materials that allow charges to move about easily are called __________.
a.
facilitators
b.
conductors
c.
insulators
d.
plastics
Hint
7.
The electric field at the location of
q'
is represented by which of the following equations?
a.
E
=
q
/Δ
V
b.
E
=
F
/
q'
c.
E
=
W
/
q
'
d.
E
=
q
'
/
F
q
'
Hint
8.
Electrons are ejected from a metal if the __________ of radiation falling on it is __________.
a.
intensity; below the threshold intensity
b.
frequency; above the threshold frequency
c.
frequency; below the threshold frequency
d.
intensity; above the threshold intensity
Hint
9.
__________ occurs when a neutral body is charged by touching it with a charged body.
a.
Charging by infusion
b.
Charging by induction
c.
Static discharge
d.
Charging by conduction
Hint
10.
The __________ is the region in which there is a high probability of finding an electron.
a.
electron cloud
b.
electron radius
c.
quantum model
d.
emission region
Hint
11.
Combined electric and magnetic fields that move through space are called __________.
a.
radiation waves
b.
piezoelectric fields
c.
oscillating fields
d.
electromagnetic waves
Hint
12.
Three particles are placed in a line. The left particle has a charge of -47
m
C, the middle, +59
m
C, and the right, -91
m
C. The middle particle is 55 cm from each of the others. What is the net force on the middle particle?
a.
77 N, right
b.
77 N, left
c.
83 N, right
d.
160 N, right
Hint
13.
Protons passing perpendicular to and without deflection through a uniform magnetic field of 0.75 T are balanced by a 3.8×10
3
-N/C electric field. What is the speed of the moving protons?
a.
3.8×10
3
m/s
b.
5.1×10
3
m/s
c.
7.5×10
3
m/s
d.
2.0×10
-5
m/s
Hint
14.
According to Figure 28-4, how many lines would appear in the visible absorption spectrum for mercury?
a.
8
b.
5
c.
9
d.
16
Hint
15.
A 35-
μ
F capacitor has an electric potential difference of 50.0 V across it. What is the charge on the capacitor?
a.
1.8×10
-3
C
b.
1.4×10
-6
C
c.
1.8×10
3
C
d.
1.75×10
-0
C
Hint
16.
_________ is the study of the properties of matter using its wave properties.
a.
Electromagnetism
b.
Quantum mechanics
c.
Thermodynamics
d.
Wave dynamics
Hint
17.
Calculate the radius of the orbital associated with the energy level
E
5
of the hydrogen atom. Use
h
2/(4
π
A24
2
Kmq
2
= 5.30×10
-11
m.
a.
1.33×10
-10
m
b.
1.33×10
-9
m
c.
1.91×10
-10
m
d.
1.91×10
-9
m
Hint
18.
The stopping potential,
V
0
, that prevents electrons from flowing across a certain photocell is 6.0 V. What is the kinetic energy in J given to the electrons by the incident light?
a.
1.60×10
-19
J
b.
6.9×10
-19
J
c.
9.6×10
-19
J
d.
6.4×10
-19
J
Hint
19.
If the charge of an atom's nucleus is +2 and the charge of the surrounding electrons is -2, the atom is __________.
a.
unstable
b.
electrically neutral
c.
negatively-charged
d.
positively-charged
Hint
20.
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
