Astronomy Today, 7e (Chaisson/McMillan)
Chapter 3 Radiation: Information from the Cosmos
Multiple-Choice
1) A wave's velocity is the product of the
A) frequency times the period of the wave.
B) period times the energy of the wave.
C) amplitude times the frequency of the wave.
D) frequency times the wavelength of the wave.
E) amplitude times the wavelength of the wave.
Answer:
See AttachmentDiff: 1
Section Ref: 3.1
2) The number of waves passing the observer per second is:
A) the wavelength in angstroms.
B) the amplitude in nm.
C) the frequency in Hertz.
D) the period in seconds.
E) the energy in milliwatts.
Answer:
See AttachmentDiff: 1
Section Ref: 3.1
3) Consider this diagram. Which statement is true?
A) The wavelength is 4.
B) The wavelength is 6.
C) The wavelength is 8.
D) The wavelength is 12.
E) The wavelength cannot be determined from this diagram.
Answer:
See AttachmentDiff: 2
Section Ref: 3.1
4) If a wave's frequency doubles, its wavelength
A) is halved.
B) is also doubled.
C) is unchanged, as c is constant.
D) is now 4x longer.
E) becomes 16x longer.
Answer:
See AttachmentDiff: 2
Section Ref: 3.1
5) Consider this diagram. Which statement is true?
A) The amplitude is 4.
B) The amplitude is 6.
C) The amplitude is 8.
D) The amplitude is 12.
E) The amplitude cannot be determined from this diagram.
Answer:
See AttachmentDiff: 2
Section Ref: 3.1
6) Both sound waves and electromagnetic radiation
A) travel at the speed of light.
B) require a medium to move through space.
C) can move through space without a medium.
D) transfer energy.
E) are transverse waves.
Answer:
See AttachmentDiff: 2
Section Ref: 3.1, 3.2
7) What does the phenomenon of diffraction demonstrate?
A) the wave nature of light
B) the polarization of light waves
C) the quantization of atomic orbitals
D) the particle nature of the photon
E) the process of ionization
Answer:
See AttachmentDiff: 1
Section Ref: Discovery 3-1
8 ) What does the phenomenon of interference demonstrate?
A) the wave nature of light
B) the polarization of light waves
C) the quantization of the atomic orbitals
D) the particle nature of the photon
E) the process of ionization
Answer:
See AttachmentDiff: 3
Section Ref: Discovery 3-1
9) Which of these is constant for ALL types of electromagnetic radiation in a vacuum?
A) amplitude
B) wavelength
C) frequency
D) velocity
E) photon energy
Answer:
See AttachmentDiff: 1
Section Ref: 3.2
10) Which statement gives the relationship between the waves in the electric and magnetic fields in an electromagnetic wave?
A) They are in phase and parallel with each other in space.
B) They are 90 degrees out of phase but parallel in space.
C) They are in phase but perpendicular to each other in space.
D) They are 180 degrees out of phase and random in their inclinations to each other.
E) They are in phase but opposite in direction of motion.
Answer:
See AttachmentDiff: 2
Section Ref: 3.2
11) Electromagnetic radiation
A) can only travel in a dense medium.
B) has only the properties of waves.
C) can behave both as a wave and as a particle.
D) is the same as a sound wave.
E) has nothing in common with radio waves.
Answer:
See AttachmentDiff: 2
Section Ref: 3.2
12) The temperature scale that places zero at the point where all atomic and molecular motion ceases is
A) fahrenheit.
B) Celsius.
C) Kelvin.
D) centigrade.
E) Ransom.
Answer:
See AttachmentDiff: 2
Section Ref: More Prec. 3-1
13) Which form of electromagnetic radiation is absorbed by carbon dioxide and water vapor in our atmosphere?
A) visible light
B) ultraviolet
C) infrared
D) radio
E) gamma rays
Answer:
See AttachmentDiff: 1
Section Ref: 3.3
14) Which form of electromagnetic radiation would be blocked in the stratosphere by ozone?
A) cosmic rays
B) ultraviolet
C) visible light
D) infrared
E) microwaves
Answer:
See AttachmentDiff: 1
Section Ref: 3.3
15) Of all the forms of electromagnetic radiation, the one with the lowest frequency is
A) gamma rays.
B) ultraviolet rays.
C) visible light.
D) microwaves.
E) radio waves.
Answer:
See AttachmentDiff: 1
Section Ref: 3.3
16) The Earth's ionosphere partially blocks which form of electromagnetic radiation?
A) gamma rays
B) ultraviolet
C) visible light
D) infrared
E) radio
Answer:
See AttachmentDiff: 1
Section Ref: 3.3
17) The two forms of electromagnetic radiation that penetrate the atmosphere best are:
A) X-rays and gamma rays.
B) ultraviolet and visible light.
C) visible and infrared light.
D) visible and radio waves.
E) infrared and microwaves.
Answer:
See AttachmentDiff: 1
Section Ref: 3.3
18 ) The hottest objects with temperatures in the millions of degrees Kelvin, give off most of their radiation in which part of the electromagnetic spectrum?
A) visible
B) radio
C) ultraviolet
D) X-ray
E) gamma ray
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
19) X-ray telescopes are located in orbit around the Earth because
A) X-ray telescopes on Earth would have to be too big.
B) X-ray telescopes are cheap and easy to launch into space.
C) there are too many X-ray telescopes on Earth, so now they are put in space.
D) X-rays don't reach the surface of Earth.
E) the X-rays that come out of the telescopes are dangerous to humans.
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
20) Electromagnetic radiation with a wavelength of 700 nm would be:
A) X-rays.
B) red light.
C) violet light.
D) ultraviolet light.
E) microwaves.
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
21) The visible color of electromagnetic radiation that has the shortest wavelength is
A) red.
B) orange.
C) green.
D) blue.
E) violet.
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
22) Colors appear different to us because of their photons' different:
A) speeds.
B) amplitudes.
C) frequencies.
D) magnetic fields.
E) polarization.
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
23) There are no X-ray telescopes on Earth because
A) they are too expensive to build
B) no one has yet invented an X-ray telescope that works
C) we can't figure out how to direct an X-ray beam through space
D) X-rays don't penetrate Earth's atmosphere
E) there are no astronomical objects that emit X-rays
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
24) There are no radio telescopes in space because
A) no one has built an antenna large enough to reach astronomical objects yet
B) radio telescopes are too fragile and expensive to make to put into space
C) there is too much radio noise in space, so a radio telescope won't work out there
D) radio waves penetrate Earth's atmosphere so there is no need to put one in space
E) you need an array, like the VLA to detect ANY radio radiation, so it is just not realistic to put an entire array in space
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
25) The radiation our eyes are most sensitive to lies in the color
A) red at 6563 Angstroms.
B) yellow-green at about 550 nm.
C) violet at 7,000 Angstroms.
D) blue at 4,321 nanometers.
E) black at 227 nm.
Answer:
See AttachmentDiff: 2
Section Ref: 3.3
26) Which type of radiation can be observed well from Earth's surface?
A) gamma ray
B) X-ray
C) ultraviolet
D) visible
E) infrared
Answer:
See AttachmentDiff: 3
Section Ref: 3.3
27) What is true of a blackbody?
A) It appears black to us, regardless of its temperature.
B) Its energy is not a continuum.
C) Its energy peaks at the wavelength determined by its temperature.
D) If its temperature doubled, the peak in its curve would be doubled in wavelength.
E) It has a complete absence of thermal energy.
Answer:
See AttachmentDiff: 1
Section Ref: 3.4
28 ) According to Wein's Law, if the surface temperature is increased by a factor of 2, its peak wavelength will
A) increase by a factor of 2.
B) decrease by a factor of 2.
C) increase by a factor of 4.
D) decrease by a factor of 4.
E) not change; Wein's law has nothing to do with peak wavelength.
Answer:
See AttachmentDiff: 1
Section Ref: 3.4
29) Star A has a temperature 1/2 that of star B, but star A is 5 times bigger than star B. Which statement below is correct?
A) Star A is redder and dimmer than star B.
B) Star A is bluer and dimmer than star B.
C) Star A is redder and brighter than star B.
D) Star A is redder and brighter than star B.
E) Star A and star B have the same color, but star A is brighter.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
30) Star A and star B have the same temperature, but different luminosities. What can you infer about these two stars?
A) Star A must be bigger.
B) Star B must be bigger.
C) Star A must be redder.
D) Star B must be redder.
E) Nothing can be inferred from the information given.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
31) Star A has a temperature 1/2 that of star B, but star A is 3 times bigger than star B. Which statement below is correct?
A) Star A is redder and dimmer than star B.
B) Star A is bluer and dimmer than star B.
C) Star A is redder and brighter than star B.
D) Star A is redder and brighter than star B.
E) Star A and star B have the same color, but star A is brighter.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
32) The total energy radiated by a blackbody depends on
A) the fourth power of its temperature.
B) the square of its temperature.
C) the square root of its temperature.
D) the cube root of its temperature.
E) the cube of its temperature.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
33) Star A and star B have the same temperature, but star B is more luminous than star A. What can you infer about these two stars?
A) Star A must be bigger.
B) Star B must be bigger.
C) Star A must be redder.
D) Star B must be redder.
E) Nothing can be inferred from the information given.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
34) At which of these Kelvin temperatures would a blackbody radiate mostly at visible wavelengths?
A) 6 K
B) 60 K
C) 600 K
D) 6000 K
E) None of these; a blackbody doesn't radiate visible light.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
35) The wavelength at which a blackbody radiates most depends on its
A) radius.
B) mass.
C) magnetic fields.
D) temperature.
E) direction of motion.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
36) Star A has a temperature 3 times that of star B. Both star A and star B are the same physical size. Which statement about star A and star B below is correct?
A) Star A is redder and dimmer than star B.
B) Star A is bluer and dimmer than star B.
C) Star A is redder and brighter than star B.
D) Star A is bluer and brighter than star B.
E) Star A and star B have the same color, but star A is brighter.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
37) Star A and star B have the same temperature, but star A is 5 times bigger than star B. Which statement below is correct?
A) Star A is redder and dimmer than star B.
B) Star A is bluer and dimmer than star B.
C) Star A is redder and brighter than star B.
D) Star A is redder and brighter than star B.
E) Star A and star B have the same color, but star A is brighter.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
38 ) Star A has a temperature 1/4 that of star B. Both star A and star B are the same physical size. Which statement below is correct?
A) Star A is redder and dimmer than star B.
B) Star A is bluer and dimmer than star B.
C) Star A is redder and brighter than star B.
D) Star A is redder and brighter than star B.
E) Star A and star B have the same color, but star A is brighter.
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
39)
Very low temperature molecular clouds emit most of their light in which part of the electromagnetic spectrum?
A) the visible
B) the X-ray
C) the ultraviolet
D) the radio
E) the infrared
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
40)
Very hot, young stars, like those in Messier 2 emit most of their light in which part of the electromagnetic spectrum?
A) the visible
B) the X-ray
C) the ultraviolet
D) the radio
E) the infrared
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
41)
A dim, young star like Herbig-Haro 68 emits most of its light in which part of the electromagnetic spectrum?
A) the visible
B) the X-ray
C) the ultraviolet
D) the radio
E) the infrared
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
42)
Stars like our Sun emit most of their light in which part of the electromagnetic spectrum?
A) the visible
B) the X-ray
C) the ultraviolet
D) the radio
E) the infrared
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
43) To see the Sun's hot corona (a temperature of 1,000,000 K, which part of the electromagnetic spectrum should one observe?
A) the visible
B) the X-ray
C) the ultraviolet
D) the radio
E) the infrared
Answer:
See AttachmentDiff: 2
Section Ref: 3.4
44) Increasing the temperature of a blackbody by a factor of 3 will increase its energy by a factor of
A) 3
B) 6
C) 9
D) 12
E) 81
Answer:
See AttachmentDiff: 3
Section Ref: 3.4
45) Increasing the temperature of a blackbody by a factor of 2 will increase its energy by a factor of
A)
B) 4
C) 8
D) 16
E) 32
Answer:
See AttachmentDiff: 3
Section Ref: 3.4