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More Beer Kegs for Students

Celebrating the end of their Physics 51 exam, three students decide to study Bernoulli's equation with their beer keg. First they pump it up so that there are 1.03 atmospheres of pressure inside the tank at the top (recall 1 atm = $10^5$ N/m$^2$). Then one punches a small (Hint: Toricelli's Law) hole near the bottom of the keg, $H = 0.5$ meters below the surface of the beer, so that the beer comes out horizontally. The other two students (A & B) lie on their backs with their open mouths $h = 0.45$ meters below the hole and $X_A = 1.0$ meters and $X_B = 1.2$ meters (respectively) horizontally in the direction of the stream. Note that all relevant distances are shown on the figure (and that all distances shown are relevant!). Assume that $\rho_{\rm beer} = 1$ gram/cc and that $g = 10$ m/sec$^2$ as usual (if you want the arithmetic to come out simple).

Which student (A or B or neither) has solved the problem correctly (and is rewarded by getting the beer)? Note that the answer is completely unimportant, what matters is how you get it!


next up previous contents
Next: Another (or the same) Up: Review Problems Previous: Yet Another Tunnel through   Contents
Robert G. Brown 2000-12-09