Question 1

What is the shortest wavelength in the Paschen series?

Accepted Answer

A)  410.2 µm 
B)  410.2 nm 
C)  820.4 nm 
D)  365 nm 
E)  820.4 µm 
A)  410.2 µm 
B)  410.2 nm 
C)  820.4 nm 
D)  365 nm 
E)  820.4 µm

Question 2

An electron is moving with the speed of $1780 \mathrm {~m} / \mathrm { s }$. What is its de Broglie wavelength? $\left( m _ { \text {electron } } = \right.$ $\left. 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $409 \mathrm {~nm}$ 
B)  $502 \mathrm {~nm}$ 
C)  $302 \mathrm {~nm}$ 
D)  $205 \mathrm {~nm}$ 
E)  $420 \mathrm {~nm}$ 
A)  $409 \mathrm {~nm}$ 
B)  $502 \mathrm {~nm}$ 
C)  $302 \mathrm {~nm}$ 
D)  $205 \mathrm {~nm}$ 
E)  $420 \mathrm {~nm}$

Question 3

A proton and an electron are both accelerated to the same final speed. If $\lambda _ { p }$ is the de Broglie wavelength of the proton and $\lambda _ { \mathrm { e } }$ is the de Broglie wavelength of the electron, then

Accepted Answer

A)  $\lambda _ { p }  \lambda _ { e }$. 
A)  $\lambda _ { p }  \lambda _ { e }$.

Question 4

Two identical metal bars are heated up until they are both glowing. One of them is "red hot" and the other is "blue hot." Which one is hotter, the one that glows red or the one that glows blue?

Accepted Answer

A)  the red one 
B)  the blue one 
C)  We cannot tell without knowing more about the two bars. 
A)  the red one 
B)  the blue one 
C)  We cannot tell without knowing more about the two bars.

Question 5

A photon scatters off of a stationary electron. Which of the following statements about the photon are true? (There could be more than one correct choice.)

Accepted Answer

A)  Its energy does not change. 
B)  Its wavelength increases due to the scattering. 
C)  Its frequency increases due to the scattering. 
D)  Its frequency decreases due to the scattering. 
E)  Its wavelength decreases due to the scattering. 
A)  Its energy does not change. 
B)  Its wavelength increases due to the scattering. 
C)  Its frequency increases due to the scattering. 
D)  Its frequency decreases due to the scattering. 
E)  Its wavelength decreases due to the scattering.

Question 6

The surface temperature of the star is 6000 K. At what wavelength is its light output a maximum? The constant in Wien's law is 0.00290 m · K.

Accepted Answer

A)  850 nm 
B)  483 nm 
C)  502 nm 
D)  311 nm 
E)  907 nm 
A)  850 nm 
B)  483 nm 
C)  502 nm 
D)  311 nm 
E)  907 nm

Question 7

What is the photon energy of red light having a wavelength of $6.40 \times 10 ^ { 2 } \mathrm {~nm} ? \left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h \right.$ $= 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s }$ )

Accepted Answer

A)  $3.11 \times 10 ^ { - 19 } \mathrm {~J}$ 
B)  $1.94 \times 10 ^ { - 19 } \mathrm {~J}$ 
C)  $1.13 \times 10 ^ { - 19 } \mathrm {~J}$ 
D)  $1.31 \times 10 ^ { - 19 } \mathrm {~J}$ 
A)  $3.11 \times 10 ^ { - 19 } \mathrm {~J}$ 
B)  $1.94 \times 10 ^ { - 19 } \mathrm {~J}$ 
C)  $1.13 \times 10 ^ { - 19 } \mathrm {~J}$ 
D)  $1.31 \times 10 ^ { - 19 } \mathrm {~J}$

Question 8

Using the Bohr model, what is the radius of the lowest-energy electron orbit in a singly-ionized He atom, which has 2 protons? ( $r _ { 1 } = 0.0529 \mathrm {~nm}$ for hydrogen)

Accepted Answer

The answer of Using the Bohr model, what is the...

Question 9

Calculate the radius of the $n = 4$ Bohr orbit in $\mathrm { O } ^ { 7 + }$ (oxygen with 7 of its 8 electrons removed). (for hydrogen, $r _ { 1 } = 0.0529 \mathrm {~nm}$ )

Accepted Answer

A)  $85 \mathrm { pm }$ 
B)  $95 \mathrm { pm }$ 
C)  $74 \mathrm { pm }$ 
D)  $106 \mathrm { pm }$ 
A)  $85 \mathrm { pm }$ 
B)  $95 \mathrm { pm }$ 
C)  $74 \mathrm { pm }$ 
D)  $106 \mathrm { pm }$

Question 10

What is the de Broglie wavelength of a ball of mass $200 \mathrm {~g}$ moving at $30 \mathrm {~m} / \mathrm { s }$ ? $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $1.1 \times 10 ^ { - 34 } \mathrm {~m}$ 
B)  $4.5 \times 10 ^ { - 28 } \mathrm {~m}$ 
C)  $2.2 \times 10^{ - 34 }\mathrm {~m}$ 
D)  $6.7 \times 10 ^{- 27} \mathrm {~m}$ 
A)  $1.1 \times 10 ^ { - 34 } \mathrm {~m}$ 
B)  $4.5 \times 10 ^ { - 28 } \mathrm {~m}$ 
C)  $2.2 \times 10^{ - 34 }\mathrm {~m}$ 
D)  $6.7 \times 10 ^{- 27} \mathrm {~m}$

Question 11

Consider the Bohr model for the hydrogen atom. $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J} \right.$, $\left. h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$
(a) How much energy (in eV) is needed to cause a transition of an electron from the second excited state to the third excited state?
(b) What wavelength photon just has enough energy to initiate the transition in (a)?

Accepted Answer

(a) 0.661

Question 12

The energy difference between adjacent orbit radii in a hydrogen atom

Accepted Answer

A)  increases with increasing values of n. 
B)  remains constant for all values of n. 
C)  varies randomly with increasing values of n. 
D)  decreases with increasing values of n. 
A)  increases with increasing values of n. 
B)  remains constant for all values of n. 
C)  varies randomly with increasing values of n. 
D)  decreases with increasing values of n.

Question 13

Electrons with a speed of $2.1 \times 10 ^ { 6 } \mathrm {~m} / \mathrm { s }$ are directed towards a $1.0 - \mu \mathrm { m }$ wide slit. An electron detector is placed $1.0 \mathrm {~m}$ behind the slit. How wide is the central maximum of the electron diffraction pattern on the detector? $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } , m _ { \text {electron } } = 9.11 \times 10 ^ { - 31 } \mathrm {~kg} \right)$

Accepted Answer

A)  $690 \mu \mathrm { m }$ 
B)  $1000 \mu \mathrm { m }$ 
C)  $1400 \mu \mathrm { m }$ 
D)  $350 \mu \mathrm { m }$ 
A)  $690 \mu \mathrm { m }$ 
B)  $1000 \mu \mathrm { m }$ 
C)  $1400 \mu \mathrm { m }$ 
D)  $350 \mu \mathrm { m }$

Question 14

Find the de Broglie wavelength of a $1.30 - \mathrm { kg }$ missile moving at $28.10 \mathrm {~m} / \mathrm { s }$. $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $2.57 \times 10 ^ { - 35 } \mathrm {~m}$ 
B)  $2.05 \times 10 ^ { - 35 } \mathrm {~m}$ 
C)  $2.28 \times 10 ^ { - 35 } \mathrm {~m}$ 
D)  $1.81 \times 10 ^ { - 35 } \mathrm {~m}$ 
A)  $2.57 \times 10 ^ { - 35 } \mathrm {~m}$ 
B)  $2.05 \times 10 ^ { - 35 } \mathrm {~m}$ 
C)  $2.28 \times 10 ^ { - 35 } \mathrm {~m}$ 
D)  $1.81 \times 10 ^ { - 35 } \mathrm {~m}$

Question 15

A metal has a work function of $4.50 \mathrm { eV }$. Find the maximum kinetic energy of the photoelectrons if light of wavelength $250 \mathrm {~nm}$ shines on the metal. $\left( 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J} , c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \right.$ × $10 - 34 \mathrm {~J} \cdot \mathrm { s }$ )

Accepted Answer

A)  $0.47 \mathrm { eV }$ 
B)  $0.37 \mathrm { eV }$ 
C)  $0.53 \mathrm { eV }$ 
D)  $0.00 \mathrm { eV }$ 
A)  $0.47 \mathrm { eV }$ 
B)  $0.37 \mathrm { eV }$ 
C)  $0.53 \mathrm { eV }$ 
D)  $0.00 \mathrm { eV }$

Question 16

In a Compton scattering experiment using $x$-rays, the wavelength of the $x$-rays increases by $5.0 \%$ as the light is scattered at an angle of $60 ^ { \circ }$ with its original direction. What was the original wavelength of the light before scattering? $\left( m _ { \text {electron } } = 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , c = 3.00 \times \right.$ $\left. 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

The answer of In a Compton scattering experiment using $x$-rays,...

Question 17

The value of a wavelength in the Balmer series is 372.1 nm. What is the corresponding value of n?

Accepted Answer

A)  6 
B)  9 
C)  3 
D)  10 
E)  14 
A)  6 
B)  9 
C)  3 
D)  10 
E)  14

Question 18

A laser emits a pulse of light that lasts $10 \mathrm {~ns}$. The light has a wavelength of $690 \mathrm {~nm}$, and each pulse has an energy of $480 \mathrm {~mJ}$. How many photons are emitted in each pulse? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = \right.$ $\left. 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $1.7 \times 10 ^ { 18 }$ 
B)  $3.1 \times 10 ^ { 43 }$ 
C)  $2.1 \times 10 ^ { 27 }$ 
D)  $2.6 \times 10 ^ { 37 }$ 
A)  $1.7 \times 10 ^ { 18 }$ 
B)  $3.1 \times 10 ^ { 43 }$ 
C)  $2.1 \times 10 ^ { 27 }$ 
D)  $2.6 \times 10 ^ { 37 }$

Question 19

A photocathode that has a work function of $2.4 \mathrm { eV }$ is illuminated with monochromatic light having photon energy $3.5 \mathrm { eV }$. What is the wavelength of this light? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \right.$. $\mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J}$ )

Accepted Answer

A)  $350 \mathrm {~nm}$ 
B)  $300 \mathrm {~nm}$ 
C)  $410 \mathrm {~nm}$ 
D)  $330 \mathrm {~nm}$ 
E)  $380 \mathrm {~nm}$ 
A)  $350 \mathrm {~nm}$ 
B)  $300 \mathrm {~nm}$ 
C)  $410 \mathrm {~nm}$ 
D)  $330 \mathrm {~nm}$ 
E)  $380 \mathrm {~nm}$

Question 20

An ionized atom having $Z$ protons has had all but one of its electrons removed. If $E$ is the total energy of the ground state electron in atomic hydrogen, then what is the total energy of the remaining electron in the ionized atom?

Accepted Answer

A)  $E / Z ^ { 2 }$ 
B)  $E$ 
C)  $Z E$ 
D)  $E / Z$ 
E)  $Z ^ { 2 } E$ 
A)  $E / Z ^ { 2 }$ 
B)  $E$ 
C)  $Z E$ 
D)  $E / Z$ 
E)  $Z ^ { 2 } E$

Exam 27: Early Quantum Theory and Models of the Atom

What is the shortest wavelength in the Paschen series?

A proton and an electron are both accelerated to the same final speed. If λp\lambda _ { p }λp​ is the de Broglie wavelength of the proton and λe\lambda _ { \mathrm { e } }λe​ is the de Broglie wavelength of the electron, then

Two identical metal bars are heated up until they are both glowing. One of them is "red hot" and the other is "blue hot." Which one is hotter, the one that glows red or the one that glows blue?

A photon scatters off of a stationary electron. Which of the following statements about the photon are true? (There could be more than one correct choice.)

The surface temperature of the star is 6000 K. At what wavelength is its light output a maximum? The constant in Wien's law is 0.00290 m · K.

Using the Bohr model, what is the radius of the lowest-energy electron orbit in a singly-ionized He atom, which has 2 protons? ( r1=0.0529 nmr _ { 1 } = 0.0529 \mathrm {~nm}r1​=0.0529 nm for hydrogen)

Calculate the radius of the n=4n = 4n=4 Bohr orbit in O7+\mathrm { O } ^ { 7 + }O7+ (oxygen with 7 of its 8 electrons removed). (for hydrogen, r1=0.0529 nmr _ { 1 } = 0.0529 \mathrm {~nm}r1​=0.0529 nm )

What is the de Broglie wavelength of a ball of mass 200 g200 \mathrm {~g}200 g moving at 30 m/s30 \mathrm {~m} / \mathrm { s }30 m/s ? (h=6.626×10−34 J⋅s)\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)(h=6.626×10−34 J⋅s)

The energy difference between adjacent orbit radii in a hydrogen atom

Find the de Broglie wavelength of a 1.30−kg1.30 - \mathrm { kg }1.30−kg missile moving at 28.10 m/s28.10 \mathrm {~m} / \mathrm { s }28.10 m/s . (h=6.626×10−34 J⋅s)\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)(h=6.626×10−34 J⋅s)

The value of a wavelength in the Balmer series is 372.1 nm. What is the corresponding value of n?

An ionized atom having ZZZ protons has had all but one of its electrons removed. If EEE is the total energy of the ground state electron in atomic hydrogen, then what is the total energy of the remaining electron in the ionized atom?

Introduction, Measurement, Estimating

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Light: Geometric Optics

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The Special Theory of Relativity

Quantum Mechanics of Atoms

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Nuclear Energy; Effects and Uses of Radiation

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Filters

A proton and an electron are both accelerated to the same final speed. If $\lambda _ { p }$ is the de Broglie wavelength of the proton and $\lambda _ { \mathrm { e } }$ is the de Broglie wavelength of the electron, then

Using the Bohr model, what is the radius of the lowest-energy electron orbit in a singly-ionized He atom, which has 2 protons? ( $r _ { 1 } = 0.0529 \mathrm {~nm}$ for hydrogen)

Calculate the radius of the $n = 4$ Bohr orbit in $\mathrm { O } ^ { 7 + }$ (oxygen with 7 of its 8 electrons removed). (for hydrogen, $r _ { 1 } = 0.0529 \mathrm {~nm}$ )

What is the de Broglie wavelength of a ball of mass $200 \mathrm {~g}$ moving at $30 \mathrm {~m} / \mathrm { s }$ ? $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Find the de Broglie wavelength of a $1.30 - \mathrm { kg }$ missile moving at $28.10 \mathrm {~m} / \mathrm { s }$ . $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

An ionized atom having $Z$ protons has had all but one of its electrons removed. If $E$ is the total energy of the ground state electron in atomic hydrogen, then what is the total energy of the remaining electron in the ionized atom?