Recent content by Mathn00b!

Homework Statement Hello, So I've got to evaluate a flux integral, but I get 0. Could someone please, check my workings and give me advice. Please find my workings and the problem attached here as an image. Thank you very much!

Thank you both for the replies!

Yes you are right, it should be 135, but really don't understand the Zc's angle. Should I do it always like that? Drawing a vector, when the real part is zero?

Could you please, explain to me how you found it to be 8 ∠90°? What formula did you use? Isnt't it the same I used at the 1st post of the thread Zc = √02 + 82 ∠tan-1 (8/0) ? and tan-1 (0) = 0. I presume it is connected since I've been asked to find it.

Strange, just sent it to one of my friends, he was able to open it. Will post a photobucket link just in a sec. I am asked to find the neutral current, which could be found from the sum of all currents, no?

Homework Statement Hello, I am given the following problem. A balanced three phase 4 wire supply has r.m.s. line voltage of 415V and supplies a star-connected load made of 3 impedances: Za = 10 - j10; Zb = 10 + j10; Zc = 0 + j8; Calculate the current phase and neutral currents, also the total...

Yes, I know its not a good practice, just wanted to see where I made a mistake, but it showed even more complicated solution and I got lost. Anyway, I found where I was wrong. It is at the differentiation of the y/√x2+y2 . I found confusing the notation with the substitution of u = x2 + y2 and...

Thanks for the reply! I tried to follow the wolfram's solution, but I got confused why they keep all the ys, I just thought that you can disregard the ys. I actually am after the partial derivative. First have to find ∂ƒ/∂xand after that for ∂ƒ/∂y. Sorry for the fact I missed to provide the...

1. I am supposed to find dx and dy. I think I am missing a step or a general idea. I spent quite some time figuring out what rules should I use and the only sequence I can think of is quotient rule and chain on the (x2 +y2)1/2 term. The answer that I find is ((xy(3x2+2y2))/(x2+y2)3/2 . On the...