Astronomy 1010 Final Exam Questions and Answers 2025

Which of the following is the phase of matter in the interior of the Sun? A) gas B) plasma C) solid D) liquid E) a mixture of all of the above -Correct Answer B) Plasma At the center of the Sun, nuclear fusion converts hydrogen into A) helium, gamma rays, and neutrinos. B) radiation and elements such as carbon and nitrogen. C) hydrogen compounds such as methane. D) radioactive elements such as uranium and plutonium. E) molecular hydrogen. -Correct Answer A) helium, gamma rays, and neutrinos. What is the only force that can overcome the repulsion between two positively charged nuclei and bind them together? A) the weak (nuclear) force B) the strong (nuclear) force C) the Coriolis force D) the electromagnetic force E) the gravitational force -Correct Answer B) The strong (nuclear) force What would happen to the core of the sun if its temperature rose slightly? A) The rate at which fusion occurs would increase, leading to a contraction of the core, which would in turn cause the temperature to rise even further. B) The rate at which fusion occurs would decrease, leading to a contraction of the core, which would in turn cause the temperature to rise even further. C) The rate at which fusion occurs would increase, leading to an expansion of the core, which would in turn cause the temperature to drop back down. D) The rate at which fusion occurs would decrease, leading to an expansion of the core, which would in turn cause the temperature to drop back down. -Correct Answer C) The rate at which fusion occurs would increase, leading to an expansion of the core, which would in turn cause the temperature to drop back down By what process does the Sun generate energy? A) gravitational contraction B) gradual expansion C) nuclear fusion D) chemical reactions E) nuclear fission -Correct Answer C) nuclear fusion Why do sunspots appear dark? A) They are composed of different elements than the rest of the sun. B) They are regions that do not emit any radiation. C) They are regions nearly devoid of gas. D) They are regions that are significantly cooler than the rest of the photosphere. -Correct Answer D) they are regions that are significantly cooler than the rest of the photosphere Which of the following statements about the sunspot cycle is not true? A) The magnetic polarity of the Sun reverses approximately every 11 years. B) At solar minimum, the first sunspots usually form at mid-latitudes on the Sun. C) The rate of nuclear fusion in the Sun peaks about every 11 years. D) The number of solar flares peaks about every 11 years. E) The number of sunspots peaks approximately every 11 years. -Correct Answer C) the rate of nuclear fusion in the sun peaks about every 11 years The light radiated from the Sun's surface reaches Earth in about 8 minutes. However, the energy of this light was released by fusion in the Sun's core about A) several thousand years ago. B) 11 years ago. C) several hundred years ago. D) 8 minutes ago. E) several hundred thousand years ago. -Correct Answer E) several hundred thousand years ago Which of the following processes is involved in the sunspot cycle? A) an imbalance in the operation of the solar thermostat B) a large change in the amount of visible light emitted by the Sun C) the winding up of magnetic field lines inside the Sun due to its differential rotation D) a slight gravitational contraction of the Sun E) small variations in the rate of nuclear energy generation in the solar interior -Correct Answer C) the winding up of magnetic field lines inside the Sun due to its differential rotation When is/was gravitational contraction an important energy generation mechanism for the Sun? A) It has played a role throughout the Sun's history, but it was most important right after nuclear fusion began in the Sun's core. B) It is the primary energy generation mechanism in the Sun today. C) It is important during periods when the Sun is going from solar maximum to solar minimum. D) It was important when the Sun was forming from a shrinking interstellar cloud of gas. -Correct Answer D) It was important when the sun was forming from a shrinking interstellar cloud of gas