Astronomy
1st Edition
ISBN: 9781938168284
Author: Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher: OpenStax
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Chapter 24, Problem 21E
Suppose you wanted to know the size of black holes with masses that are larger or smaller than the Sun. You could go through all the steps in Exercise 24.20, wrestling with a lot of large numbers with large exponents. You could be clever, however, and evaluate all the constants in the equation once and then simply vary the mass. You could even express the mass in terms of the Sun’s mass and make future calculations really easy. Show that the event horizon equation is equivalent to saying that the radius of the event horizon is equal to 3 km times the mass of the black hole in units of the Sun’s mass.
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Chapter 24 Solutions
Astronomy
Ch. 24 - How does the equivalence principle lead us to...Ch. 24 - If general relativity offers the best description...Ch. 24 - Einstein’s general theory of relativity made or...Ch. 24 - If a black hole itself emits no radiation, what...Ch. 24 - What characteristics must a binary star have to be...Ch. 24 - A student becomes so excited by the whole idea of...Ch. 24 - What is an event horizon? Does our Sun have an...Ch. 24 - What is a gravitational wave and why was it so...Ch. 24 - What are some strong sources of gravitational...Ch. 24 - Suppose the amount of mass in a black hole...
Ch. 24 - Imagine that you have built a large room around...Ch. 24 - A monkey hanging from a tree branch sees a hunter...Ch. 24 - Why would we not expect to detect X-rays from a...Ch. 24 - Look elsewhere in this book for necessary data,...Ch. 24 - Which is likely to be more common in our Galaxy:...Ch. 24 - If the Sun could suddenly collapse to a black...Ch. 24 - Suppose the people in Figure 24.4 are in an...Ch. 24 - You arrange to meet a friend at 5:00 p.m. on...Ch. 24 - You are standing on a scale in an elevator when...Ch. 24 - Look up G, c, and the mass of the Sun in Appendix...Ch. 24 - Suppose you wanted to know the size of black holes...Ch. 24 - Use the result from Exercise 24.21 to calculate...Ch. 24 - Since the force of gravity a significant distance...
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