document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1033473>Question 1033473</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help, I am very stuck, and it's a 3 part question: \r<BR>\n" );
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document.write( "Poiseuille's Law gives the rate of flow, R, of a gas through a cylindrical pipe in terms of the radius of the pipe, r,, for a fixed drop in pressure between the two ends of the pipe.\r<BR>\n" );
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document.write( "(a) Find a formula for Poiseuille's Law, given that the rate of flow is proportional to the fourth power of the radius.\r<BR>\n" );
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document.write( "Use k as the constant of proportionality.\r<BR>\n" );
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document.write( "R=\r<BR>\n" );
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document.write( "(b)  If R= 550cm3/sec in a pipe of radius cm for a certain gas, find a formula for the rate of flow of that gas through a pipe of radius r cm.\r<BR>\n" );
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document.write( "R=\r<BR>\n" );
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document.write( "(c) What is the rate of flow of the gas in part (b) through a pipe with a 7 cm radius? Round your answer to two decimal places.\r<BR>\n" );
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document.write( "R= ___ cm3/sec </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #648102 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=648102\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> *************************************************************************<BR>\n" );
document.write( "Poiseuille's Law is<BR>\n" );
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document.write( "delta R = (pi * Pressure difference * radius^4) / (8 * viscosity * length)<BR>\n" );
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document.write( "in our problem the constant of proportionality (k) is equal to (pi * Pressure difference) / (8 * viscosity * length)<BR>\n" );
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document.write( "we can find the value of k when given delta R and its associated radius<BR>\n" );
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document.write( "The problem states that delta R is proportional to the fourth power of r<BR>\n" );
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document.write( "a) delta R = k * r^4, where r is the radius and k is the constant of proportionality<BR>\n" );
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document.write( "b) 550 = k * r^4<BR>\n" );
document.write( "k = 550 / r^4<BR>\n" );
document.write( "*** we need the associated r to find the value of k, let's call it ro, then<BR>\n" );
document.write( "k = 550 / ro<BR>\n" );
document.write( "delta R = (550 / ro) * r^4<BR>\n" );
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document.write( "c) delta R = k * 7^4<BR>\n" );
document.write( "delta R = (550 / ro) * 2401<BR>\n" );
document.write( "delta R = 1320550 / ro<BR>\n" );
document.write( "*** this is as far as it goes without the value for ro<BR>\n" );
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