Question 1

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen ,
 
- The intensity of the light increases.

Accepted Answer

A)  increases 
B)  decreases 
C)  remains the same

Question 2

Suppose we have a box containing an electron with the lowest possible energy $E_{1}$. Imagine that we slowly squeeze the box, making its length $L$ smaller. What will happen to the electron's energy? The electron's energy will

Accepted Answer

A)  Increase. 
B)  Decrease. 
C)  Remain the same.

Question 3

Why (experimentally) is a set of quantons prepared in a superposition of a given observable's eigenvectors different from a classical mixture of quantons that have "already collapsed" to the different eigenvectors (with the same probabilities as predicted by the superposition)?

Accepted Answer

A)  We can (in appropriate circumstances) show that the superposition is an eigenvector of some other observable, but this is not possible for a mixture. 
B)  We can construct situations where quantons in the superposition state exhibit interference effects that cannot be observed for a mixture. 
C)  Both A and B. 
D)  Neither A nor B (explain).

Question 4

A certain organ pipe is open at both ends. Another pipe of the same length is open at one end and closed at the other. Which will have the lower pitch?

Accepted Answer

A)  The pipe open at both ends. 
B)  The pipe closed at one end. 
C)  Both will have the same pitch. 
D)  It depends on the pipes' diameters.

Question 5

Note: Each problem in this column concerns a quanton moving in one dimension in response to the potential energy function $V(x)$ shown. The graph below the potential energy graph shows the energy eigen function (EEF) $\psi_{n}(x)$ corresponding to the energy shown as a horizontal line on the potential energy graph ( $E_{n}$ means the $n$th energy level, where $n=1$ is the ground state). In each case, there is something wrong with the energy eigen function shown. Select from the following responses to indicate what is wrong:
The EEF shown is incorrectly drawn because

Accepted Answer

A)  It curves toward the axis in a forbidden region or away from the axis in an allowed region. 
B)  Its wavy part doesn't have the right number of bumps. 
C)  The amplitude of the wavy part varies incorrectly. 
D)  The wavelength of the wavy part varies incorrectly. 
E)  One of the exponential-like tails has the wrong length.

Question 6

Nuclei with the highest binding energy per nucleon $e_{b}$ have $Z$ most closely equal to what?

Accepted Answer

A)  2 
B)  4 
C)  26 
D)  60 
E)  The highest number possible
F) Other (specify)

Question 7

The earth's rotation (A) increases, (B) decreases, or (C) does not affect its gravitational binding energy.

Accepted Answer

A)  increases 
B)  decreases 
C)  does not affect its gravitational binding energy

Question 8

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen ,
 
-The value of $n$ increases (careful!).

Accepted Answer

A)  increases 
B)  decreases 
C)  remains the same

Question 9

Consider the experimental evidence we have discussed in the past few chapters. Classify the following experimental results according to the following scheme: For the quantons in question, the results:
-Light that goes through two narrow, closely spaced slits in an opaque barrier and then falls on a screen creates a pattern of multiple bright spots on the screen.

Accepted Answer

The answer of Consider the experimental evidence we have discussed...

Question 10

Consider a set of electrons with an initial spin state
$$|\psi\rangle=\left[\begin{array}{c}
\sqrt{1 / 2} \
\sqrt{1 / 2}
\end{array}\right]$$
If we send these electrons into an SGx device, what is the probability that a given electron will be determined to have its spin anti aligned with the $+x$ direction?

Accepted Answer

A)  0 
B)  $1 / 4$ 
C)  $1 / 2$ 
D)  $\sqrt{1 / 2}$ 
E)  1

Question 11

A linear traveling wave can be partially reflected when it encounters another linear traveling wave.

Accepted Answer

A) True 
 B)False

Question 12

Imagine a small magnet with its north pole vertically upward passing near the south pole of an external magnet that is above the small magnet. In what direction does the net force acting on the magnet point?

Accepted Answer

A)  Upward. 
B)  Downward. 
C)  There is zero net force. 
D)  None of the above (explain).

Question 13

According to the chart shown in figure Q13.6, how many stable isotopes of ${ }_{30} \mathrm{Zn}$ exist?

Accepted Answer

A)  One 
B)  Two 
C)  Three 
D)  Five 
E)  There is no way to determine this from the chart.

Question 14

Consider the sequence of SG devices shown in figure Q7.7. Which of the expressions below gives the proper quantum amplitude that an electron emerging from the first SG device leaves via the - channel of the final device? (Do not assume that the inner product is commutative.)

Figure 07.7

Accepted Answer

A)  $\langle+z \mid+x\rangle\langle+x \mid+\theta\rangle+\langle+z \mid-x\rangle\langle-x \mid-\theta\rangle$ 
B)  $|\langle+z \mid+x\rangle\langle+x \mid-\theta\rangle|^{2}+|\langle+z \mid-x\rangle\langle-x \mid-\theta\rangle|^{2}$ 
C)  $|\langle-\theta \mid+x\rangle\langle+x \mid+z\rangle+\langle-\theta \mid-x\rangle\langle-x \mid+z\rangle|^{2}$ 
D)  $\langle-\theta \mid+x\rangle\langle+x \mid+z\rangle+\langle-\theta \mid-x\rangle\langle-x \mid+z\rangle$ 
E)  None of the above

Question 15

As a sinusoidal wave's wavenumber increases, the wave's wavelength (in a non-dispersive medium)

Accepted Answer

A)  Increases. 
B)  Decreases. 
C)  Does not change.

Question 16

An electron moving near a proton can never be unbound, no matter what its energy might be.

Accepted Answer

A) True 
 B)False

Question 17

Suppose the energy of the longest-wavelength photon emitted by an electron in a box of length $L$ is $E_{\mathrm{ph}}$. What is the energy of the photon with the fourth-longest wavelength that might be emitted?

Accepted Answer

A)  $(4 / 3) E_{\mathrm{ph}}$ 
B)  $(5 / 3) E_{\mathrm{ph}}$ 
C)  $(7 / 3) E_{\mathrm{ph}}$ 
D)  $(8 / 3) E_{\text {ph }}$ 
E)  $3 E_{\text {ph }}$

Question 18

A free quanton with a well-defined position can also have a well-defined energy.

Accepted Answer

A) True 
 B)False

Question 19

The amount of ${ }_{18}^{40} \mathrm{Ar}$ is one-ninth the amount of ${ }_{19}^{40} \mathrm{~K}$. If the half-life of the latter is $T$, what is the rock's age?

Accepted Answer

A)  $T$ 
B)  $T / 9$ 
C)  $9 T$ 
D)  $\ln (9 T)$ 
E)  $T / \ln 9$
F) Some other result (specify)

Question 20

A quanton really has a position at all times, but quantum mechanics does not allow us to predict that position with certainty at future times as we could in Newtonian mechanics.

Accepted Answer

A) True 
 B)False

Exam 5: Matter Behaves Like Waves Quantum Physics

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen , - The intensity of the light increases.

Suppose we have a box containing an electron with the lowest possible energy $E_{1}$ . Imagine that we slowly squeeze the box, making its length $L$ smaller. What will happen to the electron's energy? The electron's energy will

Why (experimentally) is a set of quantons prepared in a superposition of a given observable's eigenvectors different from a classical mixture of quantons that have "already collapsed" to the different eigenvectors (with the same probabilities as predicted by the superposition) ?

A certain organ pipe is open at both ends. Another pipe of the same length is open at one end and closed at the other. Which will have the lower pitch?

Nuclei with the highest binding energy per nucleon $e_{b}$ have $Z$ most closely equal to what?

The earth's rotation (A) increases, (B) decreases, or (C) does not affect its gravitational binding energy.

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen , -The value of $n$ increases (careful!) .

A linear traveling wave can be partially reflected when it encounters another linear traveling wave.

Imagine a small magnet with its north pole vertically upward passing near the south pole of an external magnet that is above the small magnet. In what direction does the net force acting on the magnet point?

According to the chart shown in figure Q13.6, how many stable isotopes of ${ }_{30} \mathrm{Zn}$ exist? $According to the chart shown in figure Q13.6, how many stable isotopes of { }_{30} \mathrm{Zn} exist? A) One B) Two C) Three D) Five E) There is no way to determine this from the chart.$

As a sinusoidal wave's wavenumber increases, the wave's wavelength (in a non-dispersive medium)

An electron moving near a proton can never be unbound, no matter what its energy might be.

Suppose the energy of the longest-wavelength photon emitted by an electron in a box of length $L$ is $E_{\mathrm{ph}}$ . What is the energy of the photon with the fourth-longest wavelength that might be emitted?

A free quanton with a well-defined position can also have a well-defined energy.

The amount of ${ }_{18}^{40} \mathrm{Ar}$ is one-ninth the amount of ${ }_{19}^{40} \mathrm{~K}$ . If the half-life of the latter is $T$ , what is the rock's age?

A quanton really has a position at all times, but quantum mechanics does not allow us to predict that position with certainty at future times as we could in Newtonian mechanics.

Exam 5: Matter Behaves Like Waves Quantum Physics

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen , - The intensity of the light increases.

Suppose we have a box containing an electron with the lowest possible energy E1E_{1}E1​ . Imagine that we slowly squeeze the box, making its length LLL smaller. What will happen to the electron's energy? The electron's energy will

Why (experimentally) is a set of quantons prepared in a superposition of a given observable's eigenvectors different from a classical mixture of quantons that have "already collapsed" to the different eigenvectors (with the same probabilities as predicted by the superposition) ?

A certain organ pipe is open at both ends. Another pipe of the same length is open at one end and closed at the other. Which will have the lower pitch?

Nuclei with the highest binding energy per nucleon ebe_{b}eb​ have ZZZ most closely equal to what?

The earth's rotation (A) increases, (B) decreases, or (C) does not affect its gravitational binding energy.

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen , -The value of nnn increases (careful!) .

A linear traveling wave can be partially reflected when it encounters another linear traveling wave.

Imagine a small magnet with its north pole vertically upward passing near the south pole of an external magnet that is above the small magnet. In what direction does the net force acting on the magnet point?

According to the chart shown in figure Q13.6, how many stable isotopes of 30Zn{ }_{30} \mathrm{Zn}30​Zn exist?

Consider the sequence of SG devices shown in figure Q7.7. Which of the expressions below gives the proper quantum amplitude that an electron emerging from the first SG device leaves via the - channel of the final device? (Do not assume that the inner product is commutative.) Figure 07.7

As a sinusoidal wave's wavenumber increases, the wave's wavelength (in a non-dispersive medium)

An electron moving near a proton can never be unbound, no matter what its energy might be.

Suppose the energy of the longest-wavelength photon emitted by an electron in a box of length LLL is EphE_{\mathrm{ph}}Eph​ . What is the energy of the photon with the fourth-longest wavelength that might be emitted?

A free quanton with a well-defined position can also have a well-defined energy.

The amount of 1840Ar{ }_{18}^{40} \mathrm{Ar}1840​Ar is one-ninth the amount of 1940 K{ }_{19}^{40} \mathrm{~K}1940​ K . If the half-life of the latter is TTT , what is the rock's age?

A quanton really has a position at all times, but quantum mechanics does not allow us to predict that position with certainty at future times as we could in Newtonian mechanics.

Suppose we have a box containing an electron with the lowest possible energy $E_{1}$ . Imagine that we slowly squeeze the box, making its length $L$ smaller. What will happen to the electron's energy? The electron's energy will

Nuclei with the highest binding energy per nucleon $e_{b}$ have $Z$ most closely equal to what?

Consider a two-slit interference experiment like the one shown in figure Q3.7b. The distance between adjacent bright spots in the interference pattern on the screen , -The value of $n$ increases (careful!) .

According to the chart shown in figure Q13.6, how many stable isotopes of ${ }_{30} \mathrm{Zn}$ exist? $According to the chart shown in figure Q13.6, how many stable isotopes of { }_{30} \mathrm{Zn} exist? A) One B) Two C) Three D) Five E) There is no way to determine this from the chart.$

Suppose the energy of the longest-wavelength photon emitted by an electron in a box of length $L$ is $E_{\mathrm{ph}}$ . What is the energy of the photon with the fourth-longest wavelength that might be emitted?

The amount of ${ }_{18}^{40} \mathrm{Ar}$ is one-ninth the amount of ${ }_{19}^{40} \mathrm{~K}$ . If the half-life of the latter is $T$ , what is the rock's age?