# Physics Final

A double-slit arrangement produces interference fringes for yellow sodium light. To produce narrower-spaced fringes, should red light or blue light be used?
blue light

If the path-length difference between two identical and coherent beams is two wavelengths when they arrive on a screen, will they produce a dark or a bright spot?
bright spot

When the reflected path from one surface of a thin film is one-half wavelength different in length from the reflected path from the other surface and no phase change occurs, will the result be destructive interference or constructive interference?
destructive interference

Waves spread when passing through openings of various sizes. More spreading occurs for openings that are _______.

a) wide
b) narrow
c) either narrow or wide
d) blocked

b

Any bending of light that is not reflected or refracted is due to _______.

a) diffraction
b) Hugens wavefronts
c) fermats principle of least time
d) scattering

a

The iridescent colors seen in thin films are the result of _______.

a) refraction
b) interference
c) reflection
d) diffraction

b

A diffraction grating separates light into its component colors by the process of _______.

a) reflection
b) interference
c) refraction
d) scattering

b

A glass prism separates light into its component colors by the process of _______.

a) interference
b) scattering
c) refraction
d) reflection

c

Reinforcement and cancellation are terms common to wave _______.

a) diffraction
b) interference
c) refractions
d) reflections

b

The electric vectors that make up polarized light are _______.

a) aligned
b) in the same direction of wave travel
c) cancelled when passing through polaroid materials
d) opposite in direction to wave travel

a

Camera lenses coated with a layer of transparent material of the right thickness are almost completely non-reflective for light near the middle of the visible spectrum. They do, however, reflect a significant amount of

a) violet
b) green
c) red and violet
d) white
e) red

c

The spacings between double-slit interference fringes is increased if the slits are

a) narrower
b) farther apart
c) wider
d) closer together
e) none of these

d

A painting looks less flat when viewed with

a) one eye
b) polaroid glasses
c) both eyes

a

A thin film appears blue when illuminated with white light. The color being cancelled by destructive interference is

a) blue
b) red
c) white
d) green
e) none of these

e

Monochromatic light is light of a single

a) frequency
b) color
c) wavelength
d) all of these
e) none of these

d

When you view a soap film by white light coming from almost behind your head, you see a certain color. A friend on the other side of the film likely sees

a) the same color
b) a different color

a different color

When long-wavelength light is seen in the interference colors of a soap bubble, the wavelength being cancelled is relatively

a) long
b) short
c) neither

b

Interference colors in a soap bubble give evidence that the soap film

a) is thin
b) has two reflecting surfaces
c) both of these
d) neither of these

c

A hologram is simply a

a) pair of semi-crossed polarization filters
b) thin sheet of non-cubic transparent crystals
c) thin photographic film with microscopic images over the entire surface
d) complex diffraction grating
e) none of these

d

A property of non-cubic transparent crystals is that polarized light that travels through them

a) breaks up into two perpendicular planes
b) slows in speed
c) is rotated
d) is depolarized
e) none of these

c

The function of polarizing filters in viewing 3-D slides or movies is to provide each eye

a) the ability to see parallax
b) an independent left or right hand view
c) a stereoscopic view
d) a balanced intensity
e) with light polarized at right angles to each other

b

Viewing exact duplicates of slides in the left and right positions of a stereo projector produces

a) depth
b) no depth

b

The polarization axes of ordinary sunglasses are

a) at right angles to each other
b) vertical
c) horizontal

b

Light will not pass through a pair of Polaroids when their axes are

a) perpendicular
b) 45 degrees to each other
c) parallel
d) two of these
e) all of these

a

The vibrational direction of the electron and the plane of polarization of the light it emits

a) are the same
b) are independent of each other
c) are at right angles to each other
d) may or may not be at right angles to each other

a

Iridescent colors seen in the pearly luster of an abalone shell are due to

a) diffraction
b) dispersion
c) refraction
d) interference
e) polarization

d

Interference is a property of

a) light waves
b) water waves
c) sound waves
d) all of these
e) none of these

d

Diffraction is a result of

a) dispersion
b) reflection
c) polarization
d) interference
e) refraction

d

For viewing tiny objects in a microscope, diffraction is

b) not a factor
c) a hindrance

c

The type of radio waves that is diffracted the most around small buildings are

a) AM
b) FM
c) both diffract equally

a

Waves diffract the most when their wavelength is

a) short
b) long
c) both diffract the same

b

Diffraction is more pronounced through relatively

a) large openings
b) small openings
c) same for each

b

According to Huygens’ principle, every point on a wave

a) is the superposition of every other part of the wave
b) behaves as a source of new waves
c) is a diffraction source
d) all of these
e) none of these

b

To remove the glare of light from a polished floor, should the axis of a Polaroid filter be horizontal or vertical?

a) horizontal
b) vertical

b

When you listen to the radio, you are hearing _______.

b) visible light
c) x-rays
d) none of these

d

Of the objects listed below, which emits the most infrared radiation?

a) earth
b) a star that is the same size as the sun but is five times hotter
c) the sun

b

You look at the emission line spectrum of a gas cloud and conclude that the cloud contains mostly hydrogen (H) and a little helium (He). How do you reach this conclusion?

a) the spectrum has many more visible H emission lines than He emission lines
b) the H emission lines occur at smaller wavelengths than those of He
c) the H emission lines occur at longer wavelengths than those of He
d) the emission lines due to H are stronger than those due to He

d

If an atom contained only four energy levels, how many possible different emission lines could it emit?

a) 4
b) 5
c) 6
d) 7

c

The energy of a photon is directly proportional to its _______.

a) amplitude
b) speed
c) frequency
d) energy levels

c

To say that an atom is excited is to say it has boosted _______.

a) incandescent solids
b) molecules
c) atoms
d) electrons

d

How does the intensity at a given wavelength change if you increase the temperature?

a) the intensity increase
b) the intensity decreases
c) the intensity stays the same

a

How does the wavelength at which the maximum intensity occurs change when you increase the temperature?

a) the wavelength increase
b) the wavelength decreases
c) the wavelength stays the same

b

The peak frequency of emitted radiation is directly proportional to _______.

a) speed of travel
b) energy
c) wavelength
d) absolute temperature

d

Spectral lines seen in the solar spectrum are due to _______.

a) frequency differences
b) temperature differences
c) absorption
d) energy differences

c

The kind of lamp that is most expected to play a greater role in coming years involves _______.

a) incandescence
b) fluorescence
c) compact fluorescence
d) light-emitting diodes

d

The main difference between laser light and ordinary light involves _______.

a) frequency
b) straightness of path
c) coherence
d) color

c

As a solid is gradually heated, the first color to glow is

a) red
b) white
c) blue
d) yellow

a

The spectral lines are more distinct when viewed in a mercury vapor lamp under

a) high pressure
b) low pressure
c) same for each

b

The energy of a photon depends on its

a) amplitude
b) speed
c) frequency
d) all of these
e) none of these

c

Which light source is more energy-efficient?

a) a fluorescent lamp
b) an incandescent lamp
c) both about the same

a

Light from a phosphorescent source

a) normally has a shorter wavelength than the light that initially produced it
b) takes longer to travel from the source to you
c) is cooler than light from a fluorescent source
d) all of these
e) none of these

e

Comparing the light from a glowing tube of neon gas with light in the beam of a helium-neon laser, we find the greater number of spectral lines in light from the

a) neon gas tube
b) laser beam
c) both about the same

a

The hottest star is the star that glows

a) red
b) white
c) blue
d) cannot be determined by color alone

c

A paint pigment that absorbs red light and gives off blue light

a) is phosphorescent
b) is fluorescent
c) is polarized
d) is used in laser
e) doesn’t exist

e

A certain object emits infrared waves. If it were to emit light waves instead, its temperature would have to be

a) lower
b) the same, temperature doesn’t make any difference
c) higher

c

If light in a spectroscope passed through round holes instead of slits, spectral lines would appear

a) as thicker lines
b) dimmer
c) round

c

Green light emitted by excited mercury vapor corresponds to a particular energy transition in the mercury atom. A more energetic transition might emit

a) white light
b) blue light
c) red light
d) either red or blue light

b

Compared to the energy put into a laser, the energy of the laser beam is

a) the same
b) less
c) more

b

Astronomers can tell whether a star is approaching or receding from Earth by

a) the doppler effect
b) its change in temperature
c) its temperature
d) its absorption spectra
e) all of those

a

The dark lines in the sun’s spectrum represent light that is

a) not emitted by the sun
b) emitted by the sun
c) absorbed by the sun’s atmosphere

c

Discrete spectral lines occur when excitation takes place in a

a) liquid
b) superconducter
c) solid
d) gas
e) all of these

d

Light from two closely spaced stars will not produce a steady interference pattern at the Earth’s surface because of

a) the inherent instability of the atmosphere
b) their non-point like natures
c) incoherence
d) their different radial distances
e) closely spaced stars do produce interference patterns

c

Compared to the energy of a photon of red light, the energy of a photon of blue light is

a) the same
b) less
c) more

c

Ultraviolet light is

a) present everywhere
b) more energetic than x-rays
c) produced by crossed polaroids
d) electromagnetic energy
e) none of these

d

Which color of light carries the most energy per photon?

a) violet
b) red
c) green
d) blue
e) all the same

a

The highest frequency light of those below is

a) red
b) blue
c) violet
d) green
e) all the same

c

An atom that absorbs a photon of a certain energy can then emit

a) only a photon of the same or lower energy
b) only a photon of the same or higher energy
c) only a photon of that energy
d) a photon of any energy

a

Light is emitted when an electron

a) is boosted to a higher energy level
b) makes a transition to a lower energy level
c) neither of these

b

Light from a lit match comes from

a) protons
b) neutrons
c) electrons
d) all of these

c

Which has the greatest energy – a photon of infrared light, of visible light, or of ultraviolet light?

a) a photon of infrared light
b) a photon of visible light
c) a photon of ultraviolet light

c

The variety of colors seen in a burning log comes from the variety of

a) absorbing gases between the log and the viewer
b) electron transitions in various atoms
c) chemicals in the log
d) multi-layered incandescent surfaces
e) temperatures

b

Which has more energy – a photon of visible light or a photon of ultraviolet light?

a) a photon of visible light
b) a photon of ultraviolet light

b

If a beam of red light and a beam of blue light have exactly the same energy, which beam contains the greater number of photons?

a) a beam of red light
b) a beam of blue light

a

The phenomenon that can be explained only in terms of the particle model of light is

a) reflection
b) photoelectric effect
c) diffraction
d) refraction
e) none of the above choices are correct

b

Which of the following are conserved when a photon collides with an electron?

a) energy and velocity
b) momentum, energy, and velocity
c) momentum and velocity
d) momentum and energy
e) none of the above choices are correct

d

In the photoelectric effect, electrons ejected from bound states in the photosensitive material have

a) less kinetic energy than the absorbed photons energy
b) more kinetic energy than the absorbed photons energy
c) kinetic energy equal to the absorbed photons energy

a

An electron and a proton are traveling at the same speed. Which has the longer wavelength?

a) the proton
b) the electron
c) both have the same wavelength

b

An electron and a baseball move at the same speed. Which has the longer wavelength?

a) the electron
b) the baseball
c) both have the same wavelength

a

When the frequency of a photon is doubled, the energy it carries _______.

a) halves
b) doubles
c) remains the same
d) may be any value

b

In the equation E = hf, the h is _______.

a) a photon constant
b) a proportionality constant
c) the smallest bit of energy at frequency f
d) photon speed

b

The photoelectric effect is best stimulated by _______.

a) ultraviolet light
b) high-amplitude visible light
c) high-frequency visible light
d) infrared light

a

What exactly is ejected in the photoelectric effect?

a) low-frequency light
b) electrons
c) ultraviolet light
d) high-frequency light

b

When emitted, a photon behaves as a particle, and when traveling it behaves _______.

a) as a particle-wave
b) also as a particle
c) as a wave
d) as a wavicle

c

The wavelength of a matter wave is inversely proportional to its _______.

a) planck’s constant
b) frequency
c) kinetic energy
d) momentum

d

The entity that is simultaneously uncertain in Heisenberg’s uncertainty principle for momentum is _______.

a) the atomic level
b) energy
c) time
d) position

d

According to the correspondence principle, a new theory is valid if it

a) predicts the same results as the old theory
b) overlaps and agrees where the old theory works
c) accounts for confirmed results from the old theory
d) all of these
e) none of these

d

Which of the following forms an interference pattern when directed toward two suitably spaced slits?

a) sound
b) light
c) electrons
d) all of these
e) none of these

d

Two photons have the same wavelength. They also have the same

a) frequency
b) energy
c) both of these
d) neither of these

c

To study the energy of photoelectrons we measure

a) the distance they travel in a given time
b) the potential difference to stop them
c) their temperature
d) the time they take to go a given distance

b

A photosensitive surface is illuminated with both blue and violet light. The light that will cause the most electrons to be ejected is the

a) violet light
b) blue light
c) both eject the same number
d) not enough information given

d

In the relationship E = hf for a photon emitted from an atom, the symbol E is used to represent the energy

a) difference between atomic energy states producing the photon
b) of the emitted photon
c) both of these
d) neither of these

c

According to the uncertainty principle, the more we know about a particle’s momentum, the less we know about its

a) kinetic energy
b) speed
c) location
d) mass
e) none of these

c

Quantum uncertainties are most predominant for simultaneously measuring the speed and location of

a) an electron
b) a baseball
c) a spitball

a

Which experiment best demonstrates the particle-like nature of light?

a) photoelectric effect
b) double-slit experiment
c) neither

a

Light behaves primarily as a particle when it

a) travels from one place to another
b) interacts with matter

b

The ratio of a photon’s energy to its frequency is

a) planck’s constant
b) its amplitude
c) its wavelength
d) its speed
e) none of these

a

A lump of energy associated with light is called a

a) photon
b) quantum
c) both of these
d) neither of these

c

In the photoelectric effect, the greater the frequency of the illuminating light, the greater the

a) number of ejected electrons
b) maximum velocity of ejected electrons
c) both of these
d) neither of these

b

The photoelectric effect best demonstrates the

a) particle of nature
b) wave nature of light
c) both of these
d) none of these

a

Which has more energy per photon?

a) red light
b) blue light
c) both have the same energy

b

Which has less energy per photon?

a) red light
b) blue light
c) both have the same energy

a

In the equation E = hf, the f stands for

a) wave frequency as defined for sound, radio, and light waves
b) frequency characteristic of quantum phenomena
c) the smaller wavelengths of visible light
d) none of these

a

The ratio of the energy of a photon to its frequency is

a) not known
b) planck’s constant
c) the photon’s wavelength
d) the photon’s speed
e) pi

b

Does the de Broglie wavelength of a proton become longer or shorter as its velocity increases?

a) The de Broglie wavelength of a proton becomes longer.
b) The de Broglie wavelength of a proton becomes shorter.

b

Does the photoelectric effect depend on the wave nature or the particle nature of light?

a) wave nature
b) particle nature

b

Which laser beam carries more energy per photon – a red beam or a green beam?

a) a red beam
b) a green beam

b

Which has the greater wavelength?

a) photons emitted from an ultraviolet lamp
b) photons emitted from a TV transmitter

b

Which has the greater energy?

a) photons emitted from an ultraviolet lamp
b) photons emitted from a TV transmitter

a

Which has greater frequency?

a) photons emitted from an ultraviolet lamp
b) photons emitted from a TV transmitter

a

Which has greater momentum?

a) photons emitted from an ultraviolet lamp
b) photons emitted from a TV transmitter

a

A hypothetical atom has four distinct energy states. Assuming all transitions are possible, how many spectral lines can this atom produce?

a) 6
b) 7
c) more than 8
d) 5
e) 8

a

The quantum-mechanical probability cloud for the electron in the hydrogen atom
has an average radius

a) quite different from the radius predicted by Bohr
b) that agrees with the orbital radius of Bohr

b

The great discovery of Rutherford was _______.

a) alpha particles
b) gold atom spacing
c) the atomic nucleus
d) neutron scattering

c

The great discovery of J.J. Thompson was the _______.

a) electron
b) neutron
c) positron
d) atomic nucleus

a

The spectra of atoms reveal their _______.

a) electron structure and atomic identity
b) mass
c) nuclear structure
d) electric charge

a

A central feature of Bohr’s model of the atom is _______.

a) radiation emission due to vibrating electrons
c) its planetary reality
d) quantum jumps of energy

d

Bohr reasoned that the electrons of atoms should be viewed as _______.

a) discrete energy states
b) waves
c) tiny moons circling a planetary nucleus
d) discrete particles

a

How does the number of wavelengths vary with the orbital number of the shell?

a) The number of wavelengths decreases corresponding to the orbital number of the shell.
b) The number of wavelengths does not change with the orbital number of the shell.
c) The number of wavelengths increases corresponding to the orbital number of the shell.

c

What is the common feature among the waves associated with all of the orbital shells?

a) There is an integer number of wavelengths in each shell.
b) The waves all have the same number of wavelengths
c) the waves all have the same wavelength

a

How does the wavelength of the waves in the orbital shells change as you increase the orbital shell number?

a) the wavelength increases
b) the wavelength decrease
c) the wavelength stays the same

a

What is said to wave in the Schrodinger wave equation is _______.

a) the wave function
b) electrons as they circle the nucleus
c) probabilities
d) matter waves

a

According to Schrodinger, an electron can exist momentarily _______.

a) as several colors
b) in both space and time
c) inside the atomic nucleus
d) in atmospheric rain clouds

c

Bohr’s correspondence principle states that if a new theory is valid, it must _______.

a) produce new information
b) separate itself from older theories
c) account for the verified results of older theories
d) be consistent with the findings of quantum mechanics

c

Which color light is the result of a greater energy transition, red or blue?

a) blue
b) red

a

Quantization of electron energy states in an atom is better understood in terms of the electron’s

a) wave nature
b) particle nature
c) neither of these

a

An excited hydrogen atom is capable of emitting radiation of

a) many more than 3 frequencies
b) a single frequency
c) 3 frequencies

a

The Schrödinger equation is restricted to

a) submicroscopic particles
b) macroscopic particles
c) submicroscopic and microscopic particles
d) none of these

d

In the Bohr model of hydrogen, discrete radii and energy states result when an electron circles the atom in an integral number of

a) diffraction patterns
b) wave frequencies
c) de Broglie wavelengths
d) none of these

c

a beam of electrons has

a) particle properties
b) wave properties
c) both of these
d) neither of these

c

When Rutherford had a stream of alpha particles hit a gold foil, most of the particles

a) went almost straight through
b) spiraled
c) stopped
d) bounced back

a

Alpha particles are repelled by atomic nuclei because

a) the force between the alpha particle and the atomic nucleus is opposite to an attractive force.
b) closeness of each to each other is not permitted
c) of the repelling interaction between an alpha particle and the atomic nucleus
d) they both have the same sign of electric charge
e) none of these

d

Most alpha particles fired at a gold foil pass through undeflected because the

a) net charge of the gold atoms is zero
b) atoms of gold, like any others, are mostly empty space
c) gold atoms, unlike most other metal atoms, are relatively far apart
d) electric field is zero inside the gold
e) none of these

b

Some alpha particles fired through a gold foil bounce backward by

a) making direct hits with gold atoms
b) electrostatic repulsion when close to gold nuclei
c) electrostatic repulsion with the electron clouds of gold atoms
d) all of these
e) none of these

b

According to Niels Bohr, an electron in an excited state could give off

a) at most a single photon until the atom was excited again
b) a continuos cascade of photons for a high-level transition
c) several photons in a series of transitions to the ground state
d) none of these

c

The Bohr model of the atom is akin to a

a) central heavy ball with lighter balls connected by springs
b) miniature solar system
c) blob of plum pudding, where raisins represent atomic nuclei
d) all of these

b

We now consider the Bohr model of the atom to be

a) totally useless – of historical interest only.
b) an accurate picture of a hydrogen atom.
c) defective and oversimplified, but still useful.

c

Compared to the average diameter of a hydrogen atom, the average diameter of a helium atom is

a) smaller
b) about the same
c) larger

a

Orbital electrons do not spiral into the nucleus because of

a) the large nuclear size compared to the elections size
b) the wave nature of the electron
c) angular momentum conservation
d) electromagnetic forces
e) none of these

b

What do electrons have that protons always have in equal magnitude?

a) charge
b) energy
c) mass
d) all of these
e) none of these

a

The electrical force between an inner electron and the nucleus of an atom is larger for atoms of

a) low atomic number
b) the same for both
c) high atomic number

c

An excited atom decays to its ground state and emits a photon of green light. If instead the atom decays to an intermediate state, then the light emitted could be

a) red
b) blue
c) violet
d) any of these
e) none of these

a

Compared to the wavelengths of visible light, the wavelengths of matter waves are relatively

a) small
b) large

a

Which of these is electromagnetic radiation?

c) debris of nuclear decay

b

X-rays are most similar to which of the following – alpha, beta, or gamma rays?

a) alpha rays
b) beta rays
c) gamma rays

c

X-rays may be regarded as

a) high frequency sound waves
b) high frequency radio waves
c) both of these
d) none of these

b

Which radiation has no electric charge associated with it?

a) beta rays
b) alpha rays
c) gamma rays
d) all of these
e) none of these

c

The mass of an atomic nucleon is nearly

a) four times the mass of an electron
b) twice the mass of an electron
c) two thousand times the mass of an electron
d) a thousand times the mass of an electron

c

When a nucleus emits a beta particle, its atomic number

a) changes, and so does its mass number
b) changes, but its mass number remains constant
c) remains constant, but its mass number changes
d) remains constant, and so does its mass number
e) none of these

b

An atom with an imbalance of electrons to protons is

a) an isotope
c) a baryon
d) an ion
e) none of these

d

The atomic number of an element is the same as the number of its

a) protons
b) nucleons
c) neutrons
e)neither of these

a

Different isotopes of an element have different numbers of

a) protons
b) photons
c) neutrons
e) none of these

c

Electric forces within an atomic nucleus tend to

a) push it apart
b) hold it together
c) neither of these

a

The half-life of a radioactive substance is INDEPENDENT of

a) the number (if large enough) of atoms in the substance
b) the age of the substance
c) whether the substance exists in an elementary state or in a compound
d) the temperature of the substance
e) all of these

e

When an alpha particle is ejected from a nucleus, the nucleus then has less

a) charge
b) mass
c) both of these
d) neither of these

c

When a gamma ray is emitted by a nucleus, the nucleus then has less

a) charge
b) energy
c) both of these
d) neither of these

b

Pure elements can be transformed into entirely different elements. This statement at the present time is

a) true
b) false

a

Which of the following isotopes is radioactive?

a) carbon 14
b) carbon 12
c) both are radioactive
d) neither is radioactive in nature

a

There is a greater proportion of carbon 14 in

a) new bones
b) old bones
c) same in each

a

Carbon 14 is produced in the atmosphere principally by

a) plants and animals
b) cosmic-ray bombardment
c) nitrogen bombardment
d) photosynthesis
e) none of these

b

Carbon dating requires that the object being tested contain

a) organic material
b) charcoal
c) inorganic material
d) sugar molecules
e) none of these

a

Most of the radioactivity we personally encounter comes from

a) medical x-rays
b) the natural environment
c) fallout from past and present testing of nuclear weapons
d) nuclear power plants

b

The half-life of carbon 14 is 5730 years. If a 1-gram sample of old carbon is 1/8 as radioactive as 1-gram of a current sample, then the age of the old sample is about

a) 11,500 years
b) 22,900 years
c) 17,200 years
d) 46,000 years
e) 716 years

c

A certain radioactive isotope placed near a Geiger counter registers 120 counts per minute. If the half-life of the isotope is one day, what will the count rate be at the end of four days?

a) 7.5 counts/min
b) 10 counts/min
c) 30 counts/min
d) 15 counts/min
e) 5 counts/min

a

A device that is used primarily to detect nuclear radiation is a

a) cyclotron
b) linear accelerator
c) synchrotron
d) all of the above
e) none of the above

e