Answer to Question #173053 in Physics for josh

Question

During a marathon race, a runner’s blood flow increases to 10.0 times her resting rate. Her blood’s viscosity has dropped to 95.0% of its normal value, and the blood pressure difference across the circulatory system has increased by 50.0%. By what factor has the average radii of her blood vessels increased? 

Answer 1

$Q=\frac{\Delta P\pi r^4}{8\eta l}\\r_1=\left(\frac{Q_18\eta_1l}{\Delta P_1\pi}\right)^{0.25} \\r_2=\left(\frac{Q_28\eta_2l}{\Delta P_2\pi}\right)^{0.25} \\r_2=\left(\frac{10(8)(0.95)}{1.5\pi}\right)^{0.25}r_1\\r_2=1.586r_1$