4.4 Suppose that the universe were full of regulation baseballs, each of massmpb = 0.145 kg and radius rpb = 0.0369 m. If the baseballs weredistributed uniformly throughout the universe, what number density ofbaseballs would be required to make the density equal to the criticaldensity? (Assume nonrelativistic baseballs.) Given this density ofbaseballs, how far would you be able to see, on average, before your lineof sight intersected a baseball? In fact, we can see galaxies at a distancec/Ho - 4000 Mpc; does the transparency of the universe on this lengthscale place useful limits on the number density of intergalacticbaseballs? (Note to readers outside North America or Japan: feel free tosubstitute regulation cricket balls, with mer = 0.160 kg and rer = 0.0360m.)

Given: The mass of baseball is 0.145 kg. The radius is 0.0369 m. Let m be the mass of…

Answered: 0.145 kg and radius rh = 0.0369 m. If…

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Subject: physics