Question : The most explosive events to occur on the Sun : 2161588
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
41) The most explosive events to occur on the Sun are ________.
A) solar flares
C) solar winds
42) The source of the Sun's energy is ________.
A) nuclear fission
B) nuclear fusion
C) heat of contraction
D) potential energy
E) chemical burning
43) The most conspicuous features on the surface of the Sun are dark areas called ________.
C) helium lines
44) The Sun produces energy by converting ________.
A) oxygen nuclei to carbon dioxide
B) carbon monoxide to oxygen nuclei
C) oxygen nuclei to nitrogen nuclei
D) hydrogen nuclei to helium nuclei
E) helium nuclei to hydrogen nuclei
45) The amount of energy released during a nuclear reaction was determined by ________.
A) Niels Bohr
B) Sir Isaac Newton
C) George Hale
D) Albert Einstein
46) Streams of protons and electrons emitted from the Sun produce ________.
C) the solar wind
47) During periods of high solar activity, huge cloudlike structures that appear as great arches extending from the Sun are often produced. These solar features are called ________.
E) the solar wind
48) How do astronomers save their eyes when looking at the Sun through a telescope?
A) They project the telescope image onto a large screen or record the image with a camera.
B) They use heavy filters to block out light, particularly at specific wavelengths.
C) They look at the image very quickly.
D) They use a special water cooled camera system to avoid superheating the camera.
49) Irregularities in brightness on the Sun's photosphere (granules) are produced by ________.
A) large convective cells within the photosphere
B) pods of solid mass ejected to the photosphere by violent explosions within the Sun's interior, hence the name granule
C) local violent explosions within the photosphere equivalent to a hydrogen bomb explosion
D) different elemental abundances being stirred within the photosphere, to produce variable brightness
50) The part of the Sun clearly visible during a solar eclipse is ________.
A) the corona
B) the photosphere
C) the chromospheres
D) the mesosphere
51) The solar wind originates from ________.
A) the corona
B) the heliosphere
C) the photosphere
D) the interior of the Sun
52) There are websites that predict solar weather, or essentially the impact of the solar wind on earth. How is this possible when the speed of light is a fixed quantity?
A) The solar forecast is like weather forecasting on Earth; solar scientists observe phenomena as they form and grow on the sun, and predict their timing.
B) The solar weather effect on Earth depends largely on the earth's magnetic field and its interaction with Earth weather, so scientists predict variations in both.
C) The solar wind does not travel at the speed of light, so it arrives much later than when a solar event is observed.
D) The solar weather is related to sunspots, and they only affect Earth when the sunspots are in line with the earth, so knowing the solar rotation speed, you can predict when sunspots are aimed at Earth.
53) The corona is about ________ degrees Kelvin.
A) 1 million
54) The frequency of sunspots and related solar activity is ________.
A) a 7 year cycle
B) a 22 year cycle
C) an 11 year cycle
D) not a regular cycle
55) Prominences and solar flares present dangers to astronauts primarily because ________.
A) they can overheat the spacecraft
B) they disrupt communications on Earth
C) they do not pose a danger to astronauts
D) they pose a radiation danger from X-rays and gamma rays, but primarily from high-energy particle emissions
56) If solar flares pose a danger to orbiting spacecraft and astronauts, how much warning is there for the danger?
A) There is no warning; the radiation arrives at the same time as the feature is observed because they all travel at the speed of light.
B) The primary danger is from high energy particles that travel at the speed of the solar wind 500km/s, so there is ample warning of 3-5 days.
C) The danger is primarily from emission of neutrinos, which move at just below the speed of light; hence the warning is only a few seconds after a feature is observed.
D) The danger is from high energy particles moving thousands of km per second, so the warning is a few hours.
57) Hale discovered that sunspots were associated with magnetic fields. What happens to these magnetic fields during a full sunspot cycle?
A) They change polarity.
B) They die away.
C) They get stronger.
D) They get weaker.
58) If you live at high latitude, when do you expect to see the aurora?
A) during low sun spot activity, when solar flares are most abundant
B) at times of high sunspot activity, during the active sun
C) at intermediate periods when sunspots are present but not prominent
D) at times when the earth's magnetic field has temporarily been weakened
59) Hydrogen "burning" in stars is ________.
A) an atomic reaction that fuses 4 protons to make a helium nucleus, releasing energy by converting mass to energy
B) a chemical reaction that bonds hydrogen to oxygen to make water, which remains a gas because of the extremely high temperatures
C) an atomic reaction that generates hydrogen by splitting helium atoms
D) hydrogen atoms that combine with deuterium atoms to make HD complexes, and this reaction generates immense amounts of energy
60) What does Einstein's formula e = mc2 have to do with the Sun?
A) It determines the energy released when 4 protons are fused to make a helium atom in the interior of the Sun.
B) It determines the energy released as the solar mass is converted to energy as matter is intensely compressed in its interior.
C) It relates to how much energy is carried away from the Sun when mass is ejected from the Sun at the speed c.
D) The formula has nothing to do with the Sun.