Question 1

What is the ionization energy of the neutral hydrogen atom?

Accepted Answer

A)  $6.8 \mathrm { eV }$ 
B)  $13.6 \mathrm { eV }$ 
C)  $27.2 \mathrm { eV }$ 
D)  none of the given answers 
A)  $6.8 \mathrm { eV }$ 
B)  $13.6 \mathrm { eV }$ 
C)  $27.2 \mathrm { eV }$ 
D)  none of the given answers

Question 2

What is the longest wavelength in the Paschen series?

Accepted Answer

A)  2.01 µm 
B)  365 nm 
C)  2.01 nm 
D)  1.88 nm 
E)  1.88 µm 
A)  2.01 µm 
B)  365 nm 
C)  2.01 nm 
D)  1.88 nm 
E)  1.88 µm

Question 3

A laser pulse of duration $25 \mathrm {~ms}$ has a total energy of $1.4 \mathrm {~J}$. If the wavelength of this radiation is 567 $\mathrm { nm }$, how many photons are emitted in one pulse? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $9.9 \times 10 ^ { 19 }$ 
B)  $1.6 \times 10 ^ { 17 }$ 
C)  $3.2 \times 1017$ 
D)  $4.8 \times 10 ^ { 19 }$ 
E)  $4.0 \times 10 ^ { 18 }$ 
A)  $9.9 \times 10 ^ { 19 }$ 
B)  $1.6 \times 10 ^ { 17 }$ 
C)  $3.2 \times 1017$ 
D)  $4.8 \times 10 ^ { 19 }$ 
E)  $4.0 \times 10 ^ { 18 }$

Question 4

An 84-kW AM radio station broadcasts at $1000 \mathrm { kHz }$. How many photons are emitted each second by the transmitting antenna? $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

A)  $1.4 \times 1015$ 
B)  $6.3 \times 10 ^ { 12 }$ 
C)  $2.9 \times 10^{24}$ 
D)  $1.3 \times 10 ^ { 32 }$ 
A)  $1.4 \times 1015$ 
B)  $6.3 \times 10 ^ { 12 }$ 
C)  $2.9 \times 10^{24}$ 
D)  $1.3 \times 10 ^ { 32 }$

Question 5

At what rate are photons emitted by a 50.0-W sodium vapor lamp if it is producing monochromatic light of wavelength $589 \mathrm {~nm} ? \left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

The answer of At what rate are photons emitted by...

Question 6

If light excites atomic hydrogen from its lowest energy level to the $n = 12$ level, what is the energy of the photons of this light?

Accepted Answer

A)  $32.2 \mathrm { eV }$ 
B)  $0.0944 \mathrm { eV }$ 
C)  $1.13 \mathrm { eV }$ 
D)  $13.5 \mathrm { eV }$ 
E)  $13.6 \mathrm { eV }$ 
A)  $32.2 \mathrm { eV }$ 
B)  $0.0944 \mathrm { eV }$ 
C)  $1.13 \mathrm { eV }$ 
D)  $13.5 \mathrm { eV }$ 
E)  $13.6 \mathrm { eV }$

Question 7

If the surface of our bodies is at $37 ^ { \circ } \mathrm { C }$ what wavelength does the radiation that we emit
peak if we behave like a blackbody? The constant in Wien's law is 0.0029 m · K.

Accepted Answer

The answer of If the surface of our bodies is...

Question 8

If an electron has the same de Broglie wavelength as the wavelength of a $390 - \mathrm { nm }$ photon in vacuum, what is the speed of the electron? (melectron $= 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626$ $\times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s }$ )

Accepted Answer

A)  $2100 \mathrm {~m} / \mathrm { s }$ 
B)  $1900 \mathrm {~m} / \mathrm { s }$ 
C)  $1700 \mathrm {~m} / \mathrm { s }$ 
D)  $540 \mathrm {~m} / \mathrm { s }$ 
E)  $1500 \mathrm {~m} / \mathrm { s }$ 
A)  $2100 \mathrm {~m} / \mathrm { s }$ 
B)  $1900 \mathrm {~m} / \mathrm { s }$ 
C)  $1700 \mathrm {~m} / \mathrm { s }$ 
D)  $540 \mathrm {~m} / \mathrm { s }$ 
E)  $1500 \mathrm {~m} / \mathrm { s }$

Question 9

If the wavelength of a photon is doubled, what happens to its energy?

Accepted Answer

A)  It stays the same. 
B)  It is increased to four times its original value. 
C)  It is doubled. 
D)  It is reduced to one-fourth of its original value. 
E)  It is reduced to one-half of its original value. 
A)  It stays the same. 
B)  It is increased to four times its original value. 
C)  It is doubled. 
D)  It is reduced to one-fourth of its original value. 
E)  It is reduced to one-half of its original value.

Question 10

What is the minimum energy an incoming electron must have to knock a K shell electron $( n = 1 )$ out of an atom of molybdenum, which contains 42 protons?

Accepted Answer

A)  $44.0 \mathrm { keV }$ 
B)  $34.4 \mathrm { keV }$ 
C)  $24.0 \mathrm { keV }$ 
D)  $10.1 \mathrm { keV }$ 
E)  $11.3 \mathrm { keV }$ 
A)  $44.0 \mathrm { keV }$ 
B)  $34.4 \mathrm { keV }$ 
C)  $24.0 \mathrm { keV }$ 
D)  $10.1 \mathrm { keV }$ 
E)  $11.3 \mathrm { keV }$

Question 11

If a hydrogen atom originally in a state with principal quantum number n is excited to state n' = 2n, then

Accepted Answer

A)  its radius will quadruple and the binding energy will double. 
B)  its radius will quadruple and the binding energy will be reduced by a factor of four. 
C)  its radius and binding energy will quadruple. 
D)  its radius and binding energy will double. 
E)  its radius will double and the binding energy will quadruple. 
A)  its radius will quadruple and the binding energy will double. 
B)  its radius will quadruple and the binding energy will be reduced by a factor of four. 
C)  its radius and binding energy will quadruple. 
D)  its radius and binding energy will double. 
E)  its radius will double and the binding energy will quadruple.

Question 12

A proton that is moving freely has a wavelength of $0.600 \mathrm { pm }$. ( $m _ { \text {proton } } = 1.67 \times 10 ^ { - 27 } \mathrm {~kg}$,
$$\left. e = 1.60 \times 10 ^ { - 19 } \mathrm { C } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$$
(a) What is its momentum?
(b) What is its speed?
(c) What potential difference would it have been accelerated through, starting from rest, to reach this speed?

Accepted Answer

The answer of A proton that is moving freely has...

Question 13

Atoms in crystals are typically separated by distances of $0.10 \mathrm {~nm}$. What kinetic energy must a nonrelativistic electron have, in electron-volts, in order to have a wavelength of $0.10 \mathrm {~nm}$ ? (melectron $\left. = 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J} , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

The answer of Atoms in crystals are typically separated by...

Question 14

Determine the energy of the most energetic $x$-ray you can get from an electron transition in a heavy atom having 93 protons.

Accepted Answer

A)  $0.865 \mathrm { eV }$ 
B)  $5.19 \times 10 ^ { 7 } \mathrm { eV }$ 
C)  $164 \mathrm { MeV }$ 
D)  $118 \mathrm { keV }$ 
A)  $0.865 \mathrm { eV }$ 
B)  $5.19 \times 10 ^ { 7 } \mathrm { eV }$ 
C)  $164 \mathrm { MeV }$ 
D)  $118 \mathrm { keV }$

Question 15

The human eye can just detect green light of wavelength $500 \mathrm {~nm}$ if it arrives at the retina at the rate of $2 \times 10 ^ { - 18 } \mathrm {~W}$. How many photons arrive each second? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = \right.$ $\left. 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

Accepted Answer

The answer of The human eye can just detect green...

Question 16

What frequency of electromagnetic radiation has photons of energy $4.7 \times 10 ^ { - 25 } \mathrm {~J}$ ? $( h = 6.626 \times$ 10-34 $\mathrm { J } \cdot \mathrm { s }$ )

Accepted Answer

A)  $710 \mathrm { MHz }$ 
B)  $4.7 \mathrm { MHz }$ 
C)  $1.4 \mathrm { GHz }$ 
D)  $710 \mathrm { kHz }$ 
A)  $710 \mathrm { MHz }$ 
B)  $4.7 \mathrm { MHz }$ 
C)  $1.4 \mathrm { GHz }$ 
D)  $710 \mathrm { kHz }$

Question 17

The longest wavelength of a photon that can be emitted by a hydrogen atom, for which the initial state is $n = 3$, is closest to which one of the following values? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \right.$ $\mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J}$ )

Accepted Answer

A)  $625 \mathrm {~nm}$ 
B)  $600 \mathrm {~nm}$ 
C)  $658 \mathrm {~nm}$ 
D)  $575 \mathrm {~nm}$ 
E)  $550 \mathrm {~nm}$ 
A)  $625 \mathrm {~nm}$ 
B)  $600 \mathrm {~nm}$ 
C)  $658 \mathrm {~nm}$ 
D)  $575 \mathrm {~nm}$ 
E)  $550 \mathrm {~nm}$

Question 18

A 140-keV photon strikes an electron and scatters through an angle of $120 ^ { \circ }$ from its original direction. (melectron $= 9.11 \times 10 - 31  \mathrm {~kg} , c = 3.00 \times 10 8  \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 - 34 \mathrm {~J} \cdot \mathrm { s }$ )
(a) What is the wavelength of the photon before scattering?
(b) What is the photon wavelength after scattering?

Accepted Answer

(a) 8.87 p

Question 19

Which of the following actions will increase the de Broglie wavelength of a speck of dust? (There could be more than one correct choice.)

Accepted Answer

A)  Decrease its mass. 
B)  Decrease its speed. 
C)  Increase its mass. 
D)  Increase its speed. 
E)  Decrease its momentum. 
A)  Decrease its mass. 
B)  Decrease its speed. 
C)  Increase its mass. 
D)  Increase its speed. 
E)  Decrease its momentum.

Question 20

A doubly-ionized lithium atom $\mathrm { Li } ^ { + + }$, which has 3 protons, undergoes a transition from the $n = 5$ state to the $n = 4$ state. What is the wavelength of the photon which is emitted during this
transition? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J} \right)$

Accepted Answer

A)  $650 \mathrm {~nm}$ 
B)  $350 \mathrm {~nm}$ 
C)  $550 \mathrm {~nm}$ 
D)  $750 \mathrm {~nm}$ 
E)  $450 \mathrm {~nm}$ 
A)  $650 \mathrm {~nm}$ 
B)  $350 \mathrm {~nm}$ 
C)  $550 \mathrm {~nm}$ 
D)  $750 \mathrm {~nm}$ 
E)  $450 \mathrm {~nm}$

Exam 27: Early Quantum Theory and Models of the Atom

What is the ionization energy of the neutral hydrogen atom?

What is the longest wavelength in the Paschen series?

An 84-kW AM radio station broadcasts at 1000kHz1000 \mathrm { kHz }1000kHz . How many photons are emitted each second by the transmitting antenna? (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)

If light excites atomic hydrogen from its lowest energy level to the n=12n = 12n=12 level, what is the energy of the photons of this light?

If the surface of our bodies is at 37∘C37 ^ { \circ } \mathrm { C }37∘C what wavelength does the radiation that we emit peak if we behave like a blackbody? The constant in Wien's law is 0.0029 m · K.

If the wavelength of a photon is doubled, what happens to its energy?

What is the minimum energy an incoming electron must have to knock a K shell electron (n=1)( n = 1 )(n=1) out of an atom of molybdenum, which contains 42 protons?

If a hydrogen atom originally in a state with principal quantum number n is excited to state n' = 2n, then

Determine the energy of the most energetic xxx -ray you can get from an electron transition in a heavy atom having 93 protons.

What frequency of electromagnetic radiation has photons of energy 4.7×10−25 J4.7 \times 10 ^ { - 25 } \mathrm {~J}4.7×10−25 J ? (h=6.626×( h = 6.626 \times(h=6.626× 10-34 J⋅s\mathrm { J } \cdot \mathrm { s }J⋅s )

Which of the following actions will increase the de Broglie wavelength of a speck of dust? (There could be more than one correct choice.)

Introduction, Measurement, Estimating

Describing Motion: Kinematics in One Dimension

Kinematics in Two Dimensions; Vectors

Dynamics: Newtons Laws of Motion

Circular Motion; Gravitation

Work and Energy

Linear Momentum

Rotational Motion

Static Equilibrium; Elasticity and Fracture

Fluids

Oscillations and Waves

Sound

Temperature and Kinetic Theory

Heat

The Laws of Thermodynamics

Electric Charge and Electric Field

Electric Potential

Electric Currents

Dc Circuits

Magnetism

Electromagnetic Induction and Faradays Law

Electromagnetic Waves

Light: Geometric Optics

The Wave Nature of Light

Optical Instruments

The Special Theory of Relativity

Quantum Mechanics of Atoms

Molecules and Solids

Nuclear Physics and Radioactivity

Nuclear Energy; Effects and Uses of Radiation

Elementary Particles

Astrophysics and Cosmology

Filters

An 84-kW AM radio station broadcasts at $1000 \mathrm { kHz }$ . How many photons are emitted each second by the transmitting antenna? $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

If light excites atomic hydrogen from its lowest energy level to the $n = 12$ level, what is the energy of the photons of this light?

If the surface of our bodies is at $37 ^ { \circ } \mathrm { C }$ what wavelength does the radiation that we emit peak if we behave like a blackbody? The constant in Wien's law is 0.0029 m · K.

What is the minimum energy an incoming electron must have to knock a K shell electron $( n = 1 )$ out of an atom of molybdenum, which contains 42 protons?

Determine the energy of the most energetic $x$ -ray you can get from an electron transition in a heavy atom having 93 protons.

What frequency of electromagnetic radiation has photons of energy $4.7 \times 10 ^ { - 25 } \mathrm {~J}$ ? $( h = 6.626 \times$ 10^-34 $\mathrm { J } \cdot \mathrm { s }$ )