Homework Statement
prove that with flow in a corner, with stream function ψ=Axy, particles are accelerating per \frac{DV}{Dt}=(A2(x2-y2))/r; A=const; r-distance from the center of the corner
Homework Equations
Vx=U=\frac{∂ψ}{∂y} . . Vy=V=-\frac{∂ψ}{∂x}...
206,
thanks for the help. i always forget to apply this rule.. but still this does not lead me to the answer...
so.. i Have
y=Ve^x
y'=V'e^x + Ve^x
y''=V''e^x + 2V'e^x+Ve^x
pluging back in original equations gives me
(x-1)V''e^x+2V'e^x+V'xe^x=0
setting all the members with V=0 and factoring out...
I have a problem with differential equations - 2nd order - reduction of order
my problem is as follows:
(x − 1)y" − xy' + y = 0 , x > 1 ; y_1(x) = e^x
solving this type of diff. eq. says to use y=y_1(x)V(x) which gives me y=Ve^x differentiating y gives me
y'=V'e^x &
y''=V''e^x...
vela,
thank you.. i knew i made some silly mistake...
after correcting my work i still have discrepancy in sign.. i am getting positiv, while book is saying negative..
After differentiating y I get => y'=et((c2-2c1)sin(2t)+(c1+2c2)cos(2t))
since c1=0 and y'(∏/2)=2
2=2e∏/2c2...
Homework Statement
y"-2y'+5=0, y(∏/2)=0, y'(∏/2)=2
find general solution of this diff eq
Homework Equations
The Attempt at a Solution
i have followed all of the steps for this, rather easy 2nd order diff eq, but i my solution differs from the books solution.
steps...
Andrew, thanks again for your help.
To me it does make sense what you have described. But how do i proceed with the 2nd law analysis? I do have dead state at 20 deg C and 100 kPa. How am i supposed to use this information? Restricted Dead State is used for Exergy calculation on system as a...
AM Thanks for your quick response.
I will post the text of the problem below, and doing the first part of it is not a big deal. I am confused with the same thing you are, 2nd part of it - "expanded control volume". What does that mean?
text of the problem:
A refrigerator uses...
Hi guys, I have difficulties understanding the what I need to do in this problem. I have a ideal refrigeration cycle. first part is standard calculations, work of compressor and such. Results are Temperature range between -23 and 60 degrees C. Second part is the one that i do not understand. it...