Need it fast, Mechanical Engineering

PROBLEM 1 (30 points)
Consider a Boeing 747-400 at weight close to the maximum takeo? weight (MTOW) cruising at
Mach 0.82 at an altitude of 32000 ft.
(a) How much thrust is needed to maintain cruise? Express your answer in kN and as a fraction of
the weight.
(b) What is the diameter of a sphere that would have the same drag as the Boeing 747-400 at the
same cruise conditions? How does the sphere diameter compare to the wing span of the 747?
PROBLEM 2 (30 points)
Shear stress t
Blood cells sustain serious damage (hemolysis) when they are subjected to shear stress exceeding
150 Pa. During blood transfusion, blood ?ows through a syringe needle with typical inner diameter
D= 0.603 mm. See chart at http//
It’s the 20-gauge needle). The intent is to transfuse blood as quickly as possible without damaging
the cells.
The ?ow ?eld inside the syringe needle is well approximated by Poiseuille’s law (you can look it up
in the book), which can be worked out to give the following relation between the volume ?ow rate
Q and the wall shear stress t (the wall stress is the maximum stress):
Q =
Here µ is the viscosity of the blood. Your task is to recommend to the administering doctor the
maximum permissible blood ?ow rate. Do your calculations in SI units, then convert your ?nal
answer to L/min (liters per minute, a unit that doctors understand...).
For the average human, how long will it take to replace their entire blood volume?
Posted Date: 10/4/2012 8:35:24 PM | Location : United States

Related Discussions:- Need it fast, Assignment Help, Ask Question on Need it fast, Get Answer, Expert's Help, Need it fast Discussions

Write discussion on Need it fast
Your posts are moderated
Related Questions
ULTRASONIC WELDING This is a solid state welding process for joining similar or dissimilar metals by application of high frequency vibratory energy to work pieces held togethe

Q. Can you explain Investment casting? -Investment casting produces very high surface quality and dimensional accuracy. -Investment casting is commonly used for precision eq

(a) What will happen if air filter is not used? (b) What are the components of an air filter? (c) What precautions should be followed while cleaning the air filter? (d) What grade

Heat generated uniformly in Stainless steel plate having k=20 W/m. 0 C. The thickness of the plate is 1cm and the heat generation rate is 500 MW/m 3 . If the two sides of the plate

Rankine cycle - Thermodynamics: The major problems of Carnot cycle is compressing very wet steam mixture from the condenser pressure up to boiler pressure. The trouble can be

Inlet and Exhaust Valves : Valves are commonly mushroom shaped poppet type. They are provided on the cylinder for regulation of the charge coming into the cylinder (inlet valve)

A child is twirling a 0.0106 kg ball on a string in a horizontal circle whose radius is 0.096 m. The ball travels once around the circle in 0.540 s. (a) Determine the centripeta

Forces working on dam: Let a dam retaining water as illustrated in Figure (a). What are the forces working on it? Solution The forces working on dam are as follows:

Ratio of applied stress: What should be the ratio of applied stress, s, to yield stress s Y in a large thin plate so that plastic spread along lint of crack is equal to  1 /1