
Concept explainers
The blood vascular system consists of blood vessels (arteries, arterioles, capillaries, and veins) that convey blood from the heart to the organs and back to the heart. This system should work so as to minimize the energy expended by the heart in pumping the blood. In particular, this energy is reduced when the resistance of the blood is lowered. One of Poiseuille’s Laws gives the resistance R of the blood as
where L is the length of the blood vessel, r is the radius, and C is a positive constant determined by the viscosity of the blood (Poiseuille established this law experimentally, butit also follows from Equation 8.4.2.) The figure shows a main blood vessel with radius
(a) Use poiseuille’s Law to show that the total resistance of the blood along the path ABC is
Where a and b are the distances shown in the figure.
(b) Prove that this resistance is minimized when
(c) Find the optimal branching angle (correct to the nearest degree) when the radius of the smaller blood vessel is two-thirds the radius of the larger vessel.

Want to see the full answer?
Check out a sample textbook solution
Chapter 3 Solutions
Bundle: Calculus, Loose-Leaf Version, 8th + WebAssign Printed Access Card for Stewart's Calculus, 8th Edition, Multi-Term
- 2. f(x)=√7-x 4. A manufacturer has a monthly fixed cost of $40,000 and a production cost of $8 for each unit produced. The product sells for $12 per unit. 1. What is the cost function? 2. What is the revenue function? 3. Compute the profit corresponding to 12,000 units. 5. A rectangular box is to have a square base and a volume of 20 ft3. The material for the base costs $0.30 per ft2, the material for the sides cost $0.10 per ft2, and the material for the top costs $0.20 per ft2. Letting x denote the length of one side of the base,arrow_forwardSolve using superposition principlearrow_forwardreview problems please help!arrow_forward
- 3. f(7) 3. Find the domain of each of the following functions. 1 1. f(x)=2-6x+8 2. f(x)=√√7-x 4. A manufacturer has a monthly fixed cost of $40,000 and a production cost of $8 for each unit produced. The product sells for $12 per unit.arrow_forward7. Evaluate the following limits and justify each step. (a) lim (3x²+2x+1) 1 x²+4x-12 (b) lim 1 2 x² - 2x t-√√3t+4 (c) lim t-0 4-t x²-6x+5 (d) lim (e) lim x 5 x-5 x→2 x²+2x+3 4u+1-3 (f) lim u➡2 u-2 1 (g) lim x-3 2 x 55 x - 7x4 +4 (h) lim xx 5x+2x-1 x+1 (i) lim x²-2x+5 - 7x8+4x7 +5xarrow_forward6. Given the following graph f(x). (-2,2) 2- -5 -3 -2 (-2,-1) -1 (0,1) -2- 1 (3,0) 2 3 4 5 (3,-1) א X Compute each of the following. (a) f(-2) (b) lim f(x) #129 (c) lim f(x) *→12+ (d) lim f(x) 811H (e) f(0) (f) lim f(x) 8011 (m) Is the function continuous at x = -2,0,3? Why or why not? (g) lim f(x) +0x (h) lim f(x) x 0 (i) f(3) (j) lim f(x) x-3- (k) lim f(x) x+3+ (1) lim f(x) #13arrow_forward
- 3. Compute the profit corresponding to 12,000 units. 5. A rectangular box is to have a square base and a volume of 20 ft3. The material for the base costs $0.30 per ft2, the material for the sides cost $0.10 per ft2, and the material for the top costs $0.20 per ft2. Letting a denote the length of one side of the base, find a function in the variable x giving the cost of constructing the box. 6. Given the following graph f(x).arrow_forward8. On what intervals, each function continuous? (a) f(x) = 3x11 + 4x²+1 3x²+5x-1 (b) g(x) = x²-4 X, x < 1, QTs the function f(x) continuous at = 1? Use the definition of continuity to justifyarrow_forwardreview problem please help!arrow_forward
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:CengageCollege AlgebraAlgebraISBN:9781305115545Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage LearningAlgebra and Trigonometry (MindTap Course List)AlgebraISBN:9781305071742Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
- Algebra: Structure And Method, Book 1AlgebraISBN:9780395977224Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. ColePublisher:McDougal LittellFunctions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage Learning




