Recent content by aero_zeppelin

Homework Statement A rocket nozzle is operating with a stretched out throat, (L = 50 cm and D = 10 cm). If the inlet stagnation conditions are po1 = 1 MPa and To1 = 1500 K, determine the nozzle exit velocity and mass flow for a back pressure of 30 kPa. The diameter of the nozzle at the exit...

My friend, that's the thing, I can't get past that. I stated the problem clearly: "I'm stuck trying to find out the INVERSE LAPLACE of the given Y(s) to get y(t)". There's no point in showing what I did before, it's not needed for what's after the equation I posted. Anyway, I got it. It was...

Homework Statement I'm stuck trying to find out the inverse Laplace of F(s) to get y(t) (the solution for the differential equation): Y(s) = 1 / [ (s-1)^2 + 1 ]^2 The Attempt at a Solution I tried using a translation theorem and then apply the sine formula, but the denominator...

There's no need to be condescending or puzzled about me... I just asked kindly for your help my friend. All I'm saying is that I would like to refresh that stuff and if there's a source that focuses on it, that'd be awesome. Just for the record... after high school I did something else with...

Great, I see it now... I have been practicing them actually. Do you know about any possible source where I can read more about these little "skills" needed for Physics problem solving? (trigonometry stuff, proportions, etc...). It's not something that you explicitly find in some book, but I...

Homework Statement Ok, I have everything done for this problem... I just don't understand how they got some of the distances! Just look at the uploaded images... - Where did 2/3 m come from? (The vertical distance from the support to E) - Where did 1 m come from? (The vertical distance from E...

Thank you sir ;)

Ok, I had thought about IJ before but since the solution didn't mention it I didn't count it... Now, for BE: since BC is a zero-force member, can we "ignore" it and then consider the other 3 with Rule #2?

Homework Statement Determine the zero force members in the following truss Homework Equations - If only two members meet in an unloaded joint, both are zero-force members. - If three members meet in an unloaded joint of which two are in a direct line with one another, then the third...

It's clear now, thanks a lot guys!

Ok so Shaft B is spinning... Clockwise? And Shaft A Counterclockwise? I could take them the other way also right? For consistency

So the fact that shaft B is "pointing" in the - z direction (or lies in the -z side) has nothing to do?

I don't see it quite well yet... I don't understand why for Ma we have -y and +z and for Mb we have both positive. Are the shafts the moment vectors per se? Thanks for asking!

Ok, consistency. And am I interpreting what you said correctly? About the arcing arrows..

But isn't the convention CCW = Positive and CW = Negative ? Or is this only in North America? I'm not sure if I'm imagining this correctly... My book mentions something about"an observer" at the tip of the moment vector for determining the sense of rotation. Is this what you meant? In this...