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Ch 14: Periodic Motion

Chapter 14, Problem 13

In 2005 astronomers announced the discovery of a large black hole in the galaxy Markarian 766 having clumps of matter orbiting around once every 27 hours and moving at 30,000 km/s. (a) How far are these clumps from the center of the black hole?

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welcome back everybody. We are taking a look at the first black hole ever discovered, which was cygnus X one. And we are looking at a bit of matter that is orbiting around the black hole. Now we are told that the time it takes for one total revolution is five milliseconds or 50.5 seconds. We are also told that it has an orbital speed of 1. times 10 to the eighth meters per second. And we are asked to find what the distance is between the matter and the center of the black hole. Well that distance is just going to be the radius of orbit. And we know just by our planetary equations here that our orbital speed is equal to two pi times the radius of orbit. All divided by the time it takes for one revolution, rearranging some characters around we have that our radius is equal to our orbital speed times the time it takes for one revolution. All divided by two pi. So let's plug in some numbers here We have that our radius is equal to 1.49 times eight times the time it takes a 0.5. All divided by two pi. Giving us a radius of orbit of 100 and 18.5 kilometers corresponding to answer choice B Thank you all so much for watching. Hope this video helped. We will see you all in the next one
Related Practice
Textbook Question
Cosmologists have speculated that black holes the size of a proton could have formed during the early days of the Big Bang when the universe began. If we take the diameter of a proton to be 1.0 * 10^-15 m, what would be the mass of a mini black hole?
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Textbook Question
Astronomers have observed a small, massive object at the center of our Milky Way galaxy. A ring of material orbits this massive object; the ring has a diameter of about 15 light-years and an orbital speed of about 200 km/s. (b) Observations of stars, as well as theories of the structure of stars, suggest that it is impossible for a single star to have a mass of more than about 50 solar masses. Can this massive object be a single, ordinary star?
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Textbook Question
In 2005 astronomers announced the discovery of a large black hole in the galaxy Markarian 766 having clumps of matter orbiting around once every 27 hours and moving at 30,000 km/s. (b) What is the mass of this black hole, assuming circular orbits? Express your answer in kilograms and as a multiple of our sun's mass.
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Textbook Question
In 2005 astronomers announced the discovery of a large black hole in the galaxy Markarian 766 having clumps of matter orbiting around once every 27 hours and moving at 30,000 km/s. (c) What is the radius of its event horizon?
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Textbook Question
Use the results of Example 13.5 (Section 13.3) to calculate the escape speed for a spacecraft (a) from the surface of Mars and (b) from the surface of Jupiter. Use the data in Appendix F. (c) Why is the escape speed for a spacecraft independent of the spacecraft's mass?
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