When two galaxies collide, the stars do not generally run into each other, but the gas clou do collide, triggering a burst of new star formation. a) Estimate the probability that our Sun would collide with another star in the Andromeda galaxy if a collision between the Milky Way and Andromeda happened. Assume that each galaxy has 100 billion stars exactly like the Sun, spread evenly over a circular disi with a radius of 100,000 light ears. (Hint: first calculate the total area of 100 billion circles with the radius of the Sun and then compare that total area to the area of the Galactic disk.) b) Estimate the probability of a collision between a gas cloud in our galaxy and one in the Andromeda galaxy. To simplify the problem, assume that each galaxy has 100,000 clouds of warm hydrogen gas, each with a radius of 300 light-years, spread evenly over this same disk. Use the same method as part a.

When two galaxies collide, the stars do not generally run into each other, but the gas clou do collide, triggering a burst of new star formation. a) Estimate the probability that our Sun would collide with another star in the Andromeda galaxy if a collision between the Milky Way and Andromeda happened. Assume that each galaxy has 100 billion stars exactly like the Sun, spread evenly over a circular disi with a radius of 100,000 light ears. (Hint: first calculate the total area of 100 billion circles with the radius of the Sun and then compare that total area to the area of the Galactic disk.) b) Estimate the probability of a collision between a gas cloud in our galaxy and one in the Andromeda galaxy. To simplify the problem, assume that each galaxy has 100,000 clouds of warm hydrogen gas, each with a radius of 300 light-years, spread evenly over this same disk. Use the same method as part a.

Inquiry into Physics

8th Edition

ISBN:9781337515863

Author:Ostdiek

Publisher:Ostdiek

Chapter12: Relativity, Particle Physics, And Cosmology

Section: Chapter Questions

Problem 17P

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