Back to 3.5 Addition of Velocities

3.5 Exercise 18

Avg difficulty 2.5

(a) Use the distance and velocity data in the figure to find the rate of expansion as a function of distance.

(b) If you extrapolate back in time, how long ago would all of the galaxies have been at approximately the same position? The two parts of this problem give you some idea of how the Hubble constant for universal expansion and the time back to the Big Bang are determined, respectively.

OpenStax College Physics 2e, 3.5 Addition of Velocities, exercise 18

AI Tutor

Adapted from College Physics © 2022 Rice University. Licensed under CC BY 4.0. Sources: College Physics 2e, College Physics for AP® Courses 2e. Imported at revision f98d7a7.