ast 180- ch 5 review

Most ultraviolet radiation does not penetrate to the Earth's surface. Instead it is absorbed in: A the ozone layer B the ionosphere C the region between the Earth and the Sun D stratosphere E tanning zone

A

We have two waves of light, A and B. Wave A has a higher frequency than wave B. Then wave B must have: A longer wavelength B higher speed C lower speed D shorter wavelength E this can't be determined from the information given

A

What happens as an electron falls from a higher level to a lower level in an atom? A a photon is given off B the color of the wave involved shifts to the red C a photon is absorbed D another electron from the lower level takes its place E nothing happens; electrons can only go from a lower level to a higher level

A

When a star or galaxy is moving away from us, we observe the Doppler effect by seeing the lines in its spectrum A red-shifted (shifted toward the red end of the light spectrum) B blue-shifted (shifted toward the blue or violet end of the light spectrum) C yellow-shifted (shifted so all the colors become a little bit yellower) D become darker and darker (like a blackbody) E you can't fool me, the Doppler effect only applies to motions on Earth, not to the motions of the stars and galaxies

A

Which of the following has the longest wavelength? A radio waves B visible light waves C ultraviolet waves D x-rays E you can't fool me, all these have the same wavelength

A

Which of the following statements about infrared radiation is TRUE? A it is the band of the electromagnetic spectrum where each wave or photon has the greatest energy B it was first discovered in 1800 in an experiment using sunlight and thermometers C unlike light, infrared can never travel as fast as the speed of light D while many stars give off infrared, there is nothing on Earth at the right temperature to emit it E it is the radiation responsible for giving sunburns (or in large doses, skin cancer)

B

You are alone in a large, completely dark auditorium on Earth. What kind of telescope should I use from the other side of the auditorium to detect the electromagnetic radiation emitted by your body? A visible light B infra-red C ultra-violet D black light E no telescope will be effective if I am in a dark room

B

An artist who likes working with sources of light decides to make a modern sculpture out of electrified glass tubes that contain very thin (rarified) neon gas. When the sculpture is finished, and the electricity is turned on, the tubes glow with a rich red color. What we are seeing is: A a continuous spectrum B an absorption spectrum C an emission spectrum D a Doppler shift E all of the above

C

The Balmer Series of lines in the hydrogen atom was very important in the history of physics and astronomy. What made it so important? A It helped Rutherford explain the workings of the atomic nucleus B Balmer's experiments with these lines helped prove Wien's Law C When electrons change levels to produce the Balmer series, the emitted light is in the visible part of the spectrum, so the lines were easy to see with our eyes D The Balmer series of lines can only be observed from outer space; so the competition to see these lines led to the space race E Mr. Balmer never got the Nobel prize, which made everyone in the field of spectroscopy so angry, they worked extra hard

C

The fact that each type of atom has a unique pattern of electron orbits helps explain why A some atoms don't have any isotopes B each type of atom contains different numbers of neutrons C each type of atom shows different absorption or emission spectra D most atoms don't have a ground state E astronomers have not been able to figure out what atoms stars are made of

C

This chapter discusses that light sometimes acts like a photon. What is a photon? A a charged particle in the nucleus of every atom B a kind of magnetic substance found in reflective minerals C a self-contained "packet" of electro-magnetic energy D a kind of sound that is too high frequency for the human ear to hear E you can't fool me. Einstein showed that photons were a mistake - they don't exist.

C

We observe a glowing cloud of gas in space with a spectroscope. We note that many of the familiar lines of hydrogen that we know on Earth seem to be in a different place. They are shifted toward the blue or violet end of the spectrum compared to their positions in the spectrum of glowing hydrogen gas on Earth. From this we can conclude that: A the cloud is much hotter than hydrogen on Earth B the cloud is much cooler than hydrogen on Earth C the cloud is moving toward us D the cloud is moving away from us E none of the above can be concluded from this observation.

C

Which of the following statements about photons is FALSE? A photons always travel at the speed of light B photons each carry a specific amount of energy C a photon of visible light cannot pass through the atmosphere of the Earth, and thus cannot be seen at the Earth's surface D high energy photons have a high frequency (when thought of as waves) E a gamma-ray photon carries more energy than a visible light photon

C

A fashion designer decides to bring out a new line of clothing which reflects the longest wavelength of visible light. What color will these articles of clothing be to the human eye? A yellow-green B blue C violet D red E black

D

A politician who has just said something very dumb on an AM all-talk radio station suddenly remembers the astronomy class he had in college, and starts to worry that his words are now moving outward into space at the speed of light (and will embarrass him forever). Does he have a reason to worry? A Yes, because all radio waves do travel at the speed of light and all of them escape from the Earth B No, because radio waves travel much slower than the speed of light and will take a very long time to get anywhere C No, because radio waves are all absorbed by the ozone layer in the Earth's atmosphere D No, because AM radio waves are bounced back or scattered by the ionosphere and don't get into space E Yes, because while all radio waves do not escape from the Earth, AM radio waves do

D

An astronomer observes two ordinary stars. The first one turns out to be twice as hot as the second. This means that the first one radiates: A twice as much energy as the second B roughly the same amount of energy as the second C half as much energy as the second D about 16 times the energy of the second E this problem cannot be solved with just the information we were given

D

As of the time our textbook went to press, 118 different elements had been discovered. All of the ones with atomic number over 92 have been made in physics laboratories. When element 119 (one that has not yet been identified) is found, provided it is like the other artificially made elements, it will: A have only protons, no neutrons at all B soon be used in industry to make new kinds of plastics C have one of the smallest nuclei known D only remain stable for an extremely small fraction of a second E eventually be found in the Sun (with very high quality spectrometers)

D

How could you make an ordinary atom that is minding its own business into an ion? A send an electron from the ground state to an excited state B have all the electrons in the atom drop down to the lowest available orbits C add more neutrons to its nucleus D remove one or more electrons from the atom E send the atom to Bayonne, New Jersey

D

One of the great triumphs of spectroscopy was when astronomers identified a new element in the Sun (one that was only later found on Earth). Today, this element is called: A Solarium B Hydrogen C Einsteinium D Helium E Astronomium

D

One reason that human eyes evolved to detect visible light is: A it is the band of the electromagnetic spectrum with the lowest possible energy and thus easiest to detect B it is the only band of the spectrum that can travel through a vacuum C it is the band of the spectrum which is the least Doppler shifted coming from the Sun D it is a band of the spectrum where the Sun puts out a great deal of energy E it is the band of the spectrum where the warm Earth glows the most effectively

D

Which of the following statements about the nucleus of a typical atom (such as a carbon atom in your little finger) is FALSE: A the nucleus has an overall positive charge B the nucleus takes up a very small amount of space compared to the entire atom C the nucleus contains both protons and neutrons D the nucleus repels the electrons which move around it E the nucleus contains most of the mass of the atom

D

Why do different types of atoms (elements) give off or absorb different spectral lines? A all elements have the same lines, but they are Doppler shifted by different amounts B in some elements, electrons can only move to odd numbered levels, in others only to even numbered ones C in heavier elements, diffraction spreads out the lines that the atom produces, making the colors different D because the spacing of the energy levels is different in different atoms E because some atoms do not have a ground state, while others have three or four

D

Astronomers observe a typical star using a telescope and a spectrometer. They will see: A a continuous spectrum B an absorption spectrum C an emission spectrum D a Doppler shift E more than one of the above

E

In the future, several students living on board a space station decide to have a race among different types of electromagnetic radiation. Which of the following travels through space the fastest? A visible light B radio waves C infrared D x-rays E you can't fool me, all of these travel through space at the same speed

E

Two stars are giving off electromagnetic radiation. The hotter star will: A give off more radiation at all wavelengths B will have a higher average frequency of radiation C will radiate energy at more than one wavelength D will give off a continuous spectrum of waves E all of the above

E

When white light passes from the air into a different medium such as glass, it: A is dispersed into different colors B is reflected backwards C is refracted (bent) D is Doppler shifted E more than one of the above

E

Which of the following has the greatest average energy of random atomic and molecular motion? A a cube of ice B a cube of water C a cube of steam D a cube of air (on Earth) E a cube of the Sun

E

Which of the following statements about electromagnetic radiation is FALSE? A it always spreads out at the speed of light B it is given off by all objects that are not at a temperature of absolute zero C it is typically produced when charged particles oscillate D different waves of electromagnetic radiation differ in their wavelength or frequency E the radiation consists of tiny charged particles given off by the nuclei of atoms

E