Chapters 3-5 Answers – Flashcards
Unlock all answers in this set
Unlock answersquestion
T/F: As white light passes through a prism, the red (longer) wavelengths bend less than the blue (shorter) wavelengths, so forming the rainbow of colors.
answer
True
question
T/F: Gamma Rays are a type of electromagnetic radiation.
answer
True
question
T/F: Radio waves, visible light, and X-rays are all a type of electromagnetic radiation.
answer
True
question
The temperature scale that places zero at the point where all atomic and molecular motion ceases is:
answer
Kelvin
question
What does the phenomenon of interference demonstrate?
answer
The wave nature of light.
question
The number of waves passing the observer per second is:
answer
The frequency in Hertz.
question
Which of these is constant for ALL types of electromagnetic radiation in a vacuum?
answer
Velocity
question
If a beam of blue light has a wavelength of 400 nm is emitted by an object moving away from you at 1% of the speed of light, what wavelength would you see from this light?
answer
396 nm
question
The blackbody curve of a star moving toward Earth would have its peak shifted
answer
Toward higher energies.
question
T/F: As a star's temperature increases, the frequency of peak emission also increases.
answer
True
question
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?
answer
Star A is redder and dimmer than Star B.
question
The total energy radiated by a blackbody depends on:
answer
The fourth power of its temperature.
question
An atom that has been ionized:
answer
Has more protons than electrons.
question
In Bohr's model of the atom, electrons:
answer
only make transitions between orbitals of specific energies.
question
A heavy neutral atom, such as iron, produces many spectral lines compared to light elements like hydrogen and helium. Why?
answer
Because of the larger number of electrons and corresponding energy levels, more transitions are possible.
question
If a source of light is approaching us at 3,000 km/sec, then all its waves are:
answer
Blue shifted by 1%.
question
T/F: To reach the Cassegrain focus, a hole must be cut in the center of the primary mirror.
answer
True
question
T/F: CCD detectors gather light 10-20 times faster than the most sensitive photographic film.
answer
True
question
T/F: It is much easier to build large reflectors than large refractors.
answer
True
question
A major advantage of a Newtonian reflector over a refractor is:
answer
the elimination of chromatic aberration.
question
The process occurring when photons bounce off a polished surface is called:
answer
reflection.
question
What type of telescope is the Hubble Space Telescope?
answer
Cassegrain
question
Which method of astronomical measurement is the precise measurement of brightness?
answer
Photometry
question
One advantage of the Hubble Space telescope over ground based ones is that:
answer
in orbit, it can operate close to its diffraction limit at visible wavelengths.
question
What is "seeing"?
answer
a measurement of the image quality due to air stability
question
T/F: Optical telescopes are usually used only at night, but radio telescopes can be used day or night.
answer
True
question
What is the main reason that ultraviolet astronomy must be done in space?
answer
Earth's atmosphere absorbs most ultraviolet wavelengths.
question
The detectors on the Spitzer Space Telescope were cooled to near absolute zero in order to:
answer
prevent the infrared radiation from the instruments interfering with the infrared signals from space.
question
T/F: Galaxies look the same whether viewed in visible or X-ray wavelengths.
answer
False
