August 2017

Inner Boundary Conditions

Hello Gents,

Q:/ What is the reason for letting the inner boundary condition = (-1) when solving the radial flow of infinite form of diffusivity equation, and I would like to know what would happen if I didn't equate it with (-1).

As in the attached pic: https://i.imgur.com/AVesmHM.png

and here is the original pdf if you want: http://www.pe.tamu.edu/blasingame/da..._DimLssVar.pdf

Eliminating arbitrary constants

kindly help me with my homework. eliminate the following arbitrary constants...
y= x^2 + c1 e^3x + c2 e^3x.

Applications Of Differential Equations

The radial stress p at distance r for the axis of the thick cylinder subjected to internal pressure is given by p + r (dp/dr) = A − p where A is a constant. If p = p0 at the inner wall r = r1 and is negligible (p = 0) at the outer wall r = r2 find an expression for p.

Velocity vector by resolution and composition

please help.

problem
Block 3 slides along link 2. Q2A= 3 1/2 in. Q2F=1 5/8 in.; Q4G= 1 9/16 in.; GB= 3 in.; FB= 2 in. If the velocity vector of A is 1 1/2 in. long find the velocity vector of B by resolution and composition.

thank you in advance.

substitution/elimination method help

Hi, can someone help me with my homework in circuits? After getting the KVL and collecting the equations, i got these 3 equations, i can't quite combine them to get a value for IA,IB, and IC.

Eq.1 24IA-15IB = 5
Eq.2 12IB-20IC+15IA=5
Eq.3 -27IC+20IB=-5

http://imgur.com/j5xTT0v

Can you help with the laplace transform of derivative of sin (at)

Can you help with the laplace transform of derivative of sin (at)

Elimination of arbitrary constant: $Y=C-\dfrac{\ln x}{x}$

Can someone help me about this equation?

Elimination of arbitrary constant

Y=C-ln x/x