White Dwarf Supernovae
AST 101─ Introduction to Astronomy
Final Exam
(12/21/2007)
Instructions
A. B. Answer ALL questions on your Opscan, using a #2 pencil. Make sure to include your NAME and STUDENT ID. The computer identifies you by your student ID; do not forget to include it. C. D. E. Do NOT mark your date of birth. The exam is CLOSED BOOK. You should not use any books or notes. Time: 2 HOURS and 30 MINUTES.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the ultimate fate of an isolated pulsar? A) As gravity overwhelms the neutron degeneracy pressure, it will explode as a supernova. B) It will spin ever faster, becoming a millisecond pulsar. C) The neutron degeneracy pressure will eventually …show more content…
A) All white-dwarf supernovae involve the explosion of stars of nearly the same mass. B) White-dwarf supernovae occur only among young and extremely bright stars. C) White-dwarf supernovae are common enough that we detect several every year. D) All white-dwarf supernovae have similar light curves, which makes them easy to distinguish from massive-star supernovae. E) White-dwarf supernovae are so bright that they can be detected even in very distant galaxies. 50) What do we mean by the singularity of a black hole? A) It is the center of the black hole, a place of infinite density where the known laws of physics cannot describe the conditions. B) An object can become a black hole only once, and a black hole cannot evolve into anything else. C) There are no binary black holeseach one is isolated. D) It is the "point of no return" of the black hole; anything closer than this point will not be able to escape the gravitational force of the black hole. E) It is the edge of the black hole, where one could leave the observable universe. 51) Which of the following is an example in which you are traveling at constant speed but not at constant velocity? A) driving around in a circle at exactly 100 km/hr B) rolling freely down a hill in a cart, traveling in a straight line C) jumping up and down, with a period of exactly 60 hops per minute D) driving backward at …show more content…
A) The overall structure of the universe is very uniform, but the universe must have contained some regions of higher density in order for galaxies to form. B) The temperature of the universe can be found by taking an average over the entire sky, but individual stars will create peaks in the spectrum over small angles. C) The overall structure of the universe is very uniform, but the synthesis of different elements produces varying signatures within the background spectrum. D) The overall structure of the universe is very uniform, but intervening gas between us and the era of nuclei absorbs wavelengths depending on the composition and redshift of the gas. E) Dark matter consisting of WIMPs greatly smooths out the spectrum, but the small patches of "light" matter create peaks in the spectrum. 70) A star of spectral type O lives approximately how long on the main sequence? A) 10,000 years B) 1 million years C) 1,000 years D) 1 billion years E) 100 million years 71) If you wanted to observe a molecular cloud, in which of the ranges of the electromagnetic spectrum would you most likely observe? (There are additional possibilities.) A) infrared B) gamma-ray C) X-ray D) ultraviolet E) visible 72) How do we learn about what is going on in the center of our own galaxy (the Milky Way)? A) We cannot see the galactic center with visible or ultraviolet light, but radio and X
Final Exam
(12/21/2007)
Instructions
A. B. Answer ALL questions on your Opscan, using a #2 pencil. Make sure to include your NAME and STUDENT ID. The computer identifies you by your student ID; do not forget to include it. C. D. E. Do NOT mark your date of birth. The exam is CLOSED BOOK. You should not use any books or notes. Time: 2 HOURS and 30 MINUTES.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the ultimate fate of an isolated pulsar? A) As gravity overwhelms the neutron degeneracy pressure, it will explode as a supernova. B) It will spin ever faster, becoming a millisecond pulsar. C) The neutron degeneracy pressure will eventually …show more content…
A) All white-dwarf supernovae involve the explosion of stars of nearly the same mass. B) White-dwarf supernovae occur only among young and extremely bright stars. C) White-dwarf supernovae are common enough that we detect several every year. D) All white-dwarf supernovae have similar light curves, which makes them easy to distinguish from massive-star supernovae. E) White-dwarf supernovae are so bright that they can be detected even in very distant galaxies. 50) What do we mean by the singularity of a black hole? A) It is the center of the black hole, a place of infinite density where the known laws of physics cannot describe the conditions. B) An object can become a black hole only once, and a black hole cannot evolve into anything else. C) There are no binary black holeseach one is isolated. D) It is the "point of no return" of the black hole; anything closer than this point will not be able to escape the gravitational force of the black hole. E) It is the edge of the black hole, where one could leave the observable universe. 51) Which of the following is an example in which you are traveling at constant speed but not at constant velocity? A) driving around in a circle at exactly 100 km/hr B) rolling freely down a hill in a cart, traveling in a straight line C) jumping up and down, with a period of exactly 60 hops per minute D) driving backward at …show more content…
A) The overall structure of the universe is very uniform, but the universe must have contained some regions of higher density in order for galaxies to form. B) The temperature of the universe can be found by taking an average over the entire sky, but individual stars will create peaks in the spectrum over small angles. C) The overall structure of the universe is very uniform, but the synthesis of different elements produces varying signatures within the background spectrum. D) The overall structure of the universe is very uniform, but intervening gas between us and the era of nuclei absorbs wavelengths depending on the composition and redshift of the gas. E) Dark matter consisting of WIMPs greatly smooths out the spectrum, but the small patches of "light" matter create peaks in the spectrum. 70) A star of spectral type O lives approximately how long on the main sequence? A) 10,000 years B) 1 million years C) 1,000 years D) 1 billion years E) 100 million years 71) If you wanted to observe a molecular cloud, in which of the ranges of the electromagnetic spectrum would you most likely observe? (There are additional possibilities.) A) infrared B) gamma-ray C) X-ray D) ultraviolet E) visible 72) How do we learn about what is going on in the center of our own galaxy (the Milky Way)? A) We cannot see the galactic center with visible or ultraviolet light, but radio and X