Recent content by Krokodrile

Excuse me Sir. In the class, when the teacher give us the answer of the problems, she use the △T for determinate the △U and W, so, the results was different: △T = △H / m*Cp = 500 BTU/ (8lb) (0.25 BTU/lbmF) = 250 F △U = m*Cv*△T = (8 lb) (0.18 BTU/lbmF) (250 F) = 360 BTU W = Q - △U = 500 BTU -...

Ohhh, thank you so much. I see now where its my mistake, well ;) I am happy to understand by myself this problem.

So, the Cp and Cv its very confusing for me. But, i understand what's its happening in this process, so, i use the logic and first i obtain a ecuation for obtain the final temperature ecuaticon: Q=m*C*△T Q=m*C*(T2-T1) T2=(Q+T1)/(m*C) If the process its in constant pressure, i use the Cp valor...

vf = specific volume of liquid vg = specific volume of steam so, sorry. Yep, my mistake

Quality: mass fraction of vapor in a liquid/vapor mixture vf = specific volume of steam vg = specific volume of liquid x = quality

Hello! ;) I need help with two problems. I ready resolve it, but i have a question about if a use the units of the correct way. Because got a little strange results.

And...only a last question: in the case that 5325 have a negative sign like: cos (t+5325) + 1.5 cos (t-5325) =2.5 cos (t) ?? thank you so much for you help

oh, yes. I lose my mind for a second. So, the answer would be: 2.5 cos (t+5325) ?

Hey! I am stuck in this problem, i don't know how to sum this ecuations. I remember that its possible because the direction is the same So, i try to sum like this: cos (t+5325) + 1.5 cos (t+5325) =1.5 cos (t+5325) I don't know if i fine. I thanks your help, please ;)

I tried make it better

a) Thats my mistake, i put hz in angle. b) The velocity: the teacher just give us the ecuation 0.1cos (314.16t+angle), i the formula v= 2pi/w: 2pi/0.02 c) Maybe I am wrong with the value copy, but i sure that say us 914.16 with m/s units.For the 3rd problem I'm on my own with a single "class"...

The first ecuation values i am 99% that is correct. But, in the second and three problem i don't know if my results are ok. The problem number 2 i comprobate with the teacher that te aceleration its correct, so, with this i calculate the velocity. I use like example the second problem for try...

Yes. i agree. Maybe if the second gas had mass i wold to use V = mRT/P, but this is not the case. I don't find any formule of the gases for resolve the problem. Maybe the teacher forget the mass or he volume value. This is my opinion, but, i would like know your opinion about why its not enogh...

yes, it is. The word-word statement. Meanwhile i try to resolved, i noticed that if don't have a mase or a volume value in the second gas i can't obtain all the values of that gas. But, yes, its the exact wording of the problem say be the teacher. So, i guees that its possible to resolve

Hey there! for this problem i try to use the combinate gas ecuation. First of all the values its necesary to have it in absolutes: 70 F = 527.67 K 90 F = 549.67 K The ecuation looks like: (200 psig) (1 ft^3)/529.67 K = (0.3 InHg) V2/549.67 K I can eliminate "K" but not psig with InHg for obtain...