Download Modern Physics TEST

Modern Physics TEST - HP
Equations: 𝑐 = 𝜆𝑓, 𝐸 = ℎ𝑓,
Name: ________________________________
𝑚𝑛𝑢𝑐𝑙𝑒𝑢𝑠 + 𝑚 = 𝑚𝑛𝑢𝑐𝑙𝑒𝑜𝑛𝑠 ,
Multiple Choice - Identify the choice that best completes the statement or answers the question. (2pts each)
____ 1.
Electromagnetic waves are ____ electric and magnetic fields.
a.
transverse
c.
oscillating
b.
constant
d.
parallel
____ 2.
How does an electromagnetic wave propagate itself?
a.
A changing magnetic field induces an electric field perpendicular to the magnetic
field.
b.
A changing electric field induces a magnetic field perpendicular to the electric field.
c.
Changing electric and magnetic fields produce a transverse wave that is
perpendicular to both of the oscillating fields.
d.
all of the above
____ 3.
All of the following statements about the electromagnetic force are true except which one?
a.
It is one of the four fundamental forces in the universe.
b.
It exerts a force on either charged or uncharged particles.
c.
It obeys the inverse-square law.
d.
It is produced by—and produces—electric and magnetic fields.
____ 4.
Where is energy stored in electromagnetic waves?
a.
in the wave’s moving atoms
b.
in the oscillating electric and magnetic fields
c.
in the electromagnetic force
d.
in the wave’s directional vector
____ 5. What is the frequency of a photon with an energy of 1.99  10 J?
(h = 6.63  10 Js)
a.
c.
1.32  10-52 Hz
3.00  10 Hz
-15
b.
d.
1.51 x 1027 Hz
3.33  10 Hz
____ 6.
Which interaction of nature is weakest?
a.
strong
c.
electromagnetic
b.
weak
d.
gravitational
____ 7.
The nucleus of an atom is made up of which of the following combinations of particles?
a.
electrons and protons
c.
protons, electrons, and neutrons
b.
electrons and neutrons
d.
protons and neutrons
____ 8.
To which of the following is the atomic number of a given element equivalent?
a.
the number of protons in the nucleus
b.
the number of neutrons in the nucleus
c.
the sum of the protons and neutrons in the nucleus
d.
the number of electrons in the outer shells
____ 9.
If there are 128 neutrons in Pb-210 ( 210𝑃𝑏), how many neutrons are found in the nucleus of Pb-206 ( 206𝑃𝑏?)
a.
122
c.
126
b.
124
d.
130
____ 10. What is the binding energy of a nucleus?
a.
the energy needed to remove one of the nucleons
b.
the average energy with which any nucleon is bound in the nucleus
c.
the energy released when nucleons bind together to form a stable nucleus
d.
the mass of the nucleus times c
____ 11. If the stable nuclei are plotted with neutron number versus proton number, the curve formed
by the stable nuclei does not follow the line N = Z. Which of the following influences the
binding energy so that this “valley of stability” forms? (see plot right)
a.
the volume of the nucleus
c.
the Coulomb repulsive force
b.
the size of the nuclear surface
d.
the proton-neutron mass difference
____ 12.
As the number of protons in the nucleus increases, the repulsive force
a.
becomes stronger.
c.
remains unchanged.
b.
becomes weaker.
d.
drops to zero.
____ 13.When are heavy nuclei most stable?
a.
when they contain more protons than neutrons
b.
when they contain more neutrons than protons
c.
when they contain equal numbers of protons and neutrons
d.
when the Coulomb force is stronger than the nuclear force
____ 14. In fusion reactions, how does the binding energy per nucleon vary?
a.
The binding energy per nucleon remains constant as atomic number increases.
b.
The binding energy per nucleon remains constant as atomic number decreases.
c.
The binding energy per nucleon increases as atomic number increases.
d.
The binding energy per nucleon decreases as atomic number increases.
____ 15. In order to adequately control a chain reaction, it is necessary to have within the fissionable material a
nonfissionable material. How does this material interact with neutrons?
a.
The material absorbs neutrons.
c.
The material scatters neutrons.
b.
The material emits neutrons.
d.
The material converts neutrons.
____ 16.
____ 17.
What daughter isotopes are produced when a neutron combines with a nucleus of
are also produced in the reaction.
a.
c.
b.
d.
At this time, all nuclear reactors operate through
a.
fission only.
b.
fusion only.
c.
d.
? Assume that three neutrons
both fission and fusion.
neither fission nor fusion.
Short Answer :
18.
What are the three quantities that can express the electromagnetic spectrum? (3pts)
__________________, ____________________, ____________________
19. Put in order from shortest to longest wavelength: Radio waves, Infrared waves, Gamma waves, Blue light waves?
(2pts) _____________________, _____________________, __________________, _________________
20.
What does the equation E = hf represent? ____________________________________________________ (2pts)
21.
What are atoms that have the same atomic number but different neutron numbers? ________________ (1 pt)
22.
Why do elements containing more than 83 protons have unstable nuclei? Explain. (2pts)
____________________________________________________________________________________________________
23.
What is nuclear fusion? (2pts)
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24.
In the nuclear chain reaction of uranium-235, what particle reacts with the uranium nucleus to make it unstable?
(1pt) __________________________
25.
Use pictures and words to explain what a chain reaction is in nuclear fission? (2pts)
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26.
27.
Which has more photons? 10J of Infrared light or 10 Joules of Ultraviolet light? Explain
State four different safety issues involved in nuclear power and explain each briefly:
a. _________________________________________________________________________________________
b. _________________________________________________________________________________________
c. _________________________________________________________________________________________
d. _________________________________________________________________________________________
Problem Solving:
28. What is the wavelength of a photon whose energy is 3.4 eV? (h = 6.63  10
1 eV = 1.60  10
29.
Js; c = 3.00  10 m/s;
J)
Calculate the binding energy of the iron-56 nucleus. (u = 1.661 x 10-27 kg; atomic mass of
940 u; atomic mass of
= 1.007 825 u; m = 1.008 665 u, E = mc2, c = 3 x 108) (3pts)
= 55.934
30. Short Essay: Is light a wave or a particle? Explain the evidence for each including the results of the experiments
involved. (6pts)
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