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Unformatted text preview: stationary so that u cv = u , letting denote cup number density, the Reynolds Transport Theorem tells us that dN dt = d dt 888 V dV + 8 s 8 S u n dS By definition of , necessarily N cup = $$$ dV . Also, the net flux of cups out of the control volume is 8 s 8 S u n dS = n sold + n stolen Now, the rate of change of the number of cups in the system is the rate at which cups are broken so that dN/dt = dN cup /dt , where = 0 . 05 = 1 / 20 . So, our basic conservation law is dN cup dt = dN cup dt + n sold + n stolen Since we are given n stolen = n sold , we find (1 ) dN cup dt = (1 + ) n sold Therefore, dN cup dt = w 1 + 1 W n sold Finally, since = 1 / 10 and = 1 / 20 , we conclude that dN cup dt = X 11 / 10 19 / 20 ~ n sold = 22 19 n sold...
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This note was uploaded on 02/09/2012 for the course AME 309 taught by Professor Phares during the Spring '06 term at USC.
- Spring '06