Question 1033473
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Poiseuille's Law is
:
delta R = (pi * Pressure difference * radius^4) / (8 * viscosity * length)
:
in our problem the constant of proportionality (k) is equal to (pi * Pressure difference) / (8 * viscosity * length)
: 
we can find the value of k when given delta R and its associated radius
:
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The problem states that delta R is proportional to the fourth power of r
:
a) delta R = k * r^4, where r is the radius and k is the constant of proportionality
:
b) 550 = k * r^4
k = 550 / r^4
*** we need the associated r to find the value of k, let's call it ro, then
k = 550 / ro
delta R = (550 / ro) * r^4
:
c) delta R = k * 7^4
delta R = (550 / ro) * 2401
delta R = 1320550 / ro
*** this is as far as it goes without the value for ro
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