Physics, 14.09.2019 08:30 tvrgrvJfbhh3881

The mean mass density of stars in the disk of the galaxy is observed to vary with the height z above the galactic plane as p+(z) = p4,0 e-17\/h* close to the sun, where px is the density of stars in the plane, and hx is a scale height (p+,0 and h+ are constants at the location of the sun). the density of the interstellar gas p, is also found to vary exponentially with height at the sun's location, with pg(z) = 29,0 e 17\/hg, where pg,0 and hg are constants. observations show that h+ = 250 pc, while hg =150 pc and that numerically, p+,0 = 6 p9,0. what is the ratio of the surface density of stars, et, to that of gas, eg, at the sun's distance from the galactic center? (hint: how do you convert from volume density to surface density?

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