Recent content by janger

I don't agree. These vents on new heaters are small and the exhaust is forced out under pressure. I was thinking the chimney since she lives near a river that has floating restaurants going up and down that often play music. The river already funnels sound along it. And a chimney on the roof...

Sure is. Great high frequency response (>100kHz). Check out some of the plasma speakers on youtube. http://www.youtube.com/watch?v=DTYuIHVgGYU&feature=related AFAIK the only real difference between plasma speakers and flame speakers is the way the ionization occurs.

Like this? : http://www.swtpc.com/mholley/PopularElectronics/May1968/Flame_Amplification.htm Plasma speakers (which flame speakers are a "subset" of) require some decent pre-amplified current to work I think. But I'm interested to know how much current flows through the flame sensor in a...

I was going to post a link to the "radio through speakers". But most of those problems occur in devices with a speaker. Poor grounding/shielding allows the wiring to act as an antenna, IIRC. I also searched about picking radio up through teeth fillings and haven't found any verified cases...

Yeah I'm thinking towards the flue funneling noises down. The problem with a "medical condition" is other people have apparently heard it. I'll know more when I hear it myself. Was just wondering if any of you thought it was plausible at all.

Here's a bit of a weird one. My grandmother (93 years old but "still with it" mostly) had a natural gas heater installed last year. It's one of those wall mounted heaters with a flue. Anyway, several weeks ago she told my parents she could hear the radio through it at night. I was quick to...

Sorry rcgldr, that diagram is just for the lift produced from the wing. I know there are other forces to calculate. But the important thing was that I had this right since the same equations are used for the tail etc. And yeah I have the drag force worked out too. The axes are just to show...

I was trying to work out a similar thing a couple of years ago, but it was more to do with optimizing the tank volume/pressure for given muzzle velocity. But I got stuck as it involved finding the rate of change of pressure and stuff. Simple way as you asked: If you assume a constant pressure...

This is what I have been asking. They say a picture is worth a thousand words. Is the following the correct way to calculate all the entities (explanation follows): I forgot to include the axis labels: x is red, y is green and z is blue. The yellow plane is the y-z plane, relative to...

No that's ok. We obviously don't understand one another. :) My problem isn't with the basics here. I have both global and local matrices and all that stuff. The "math" part is not giving me a headache. That's all fine. It's simply which angles/vectors/vector components etc to use in the...

Right, so you're saying you basically zero out any side wind component when calculating AoA? From my previous calculations: The wing's chord points along the z-axis = <0,0,1>, v(rel) = <30, -10, 95.4> Therefore, AoA is the angle between <0,0,1> and <0, -10, 95.4>. And not between <0,0,1>...

Haha, that's what I'm trying to do rcgldr. Keep it simple :) "the wind that flows opposite of the direction of the aircraft" is obviously what I showed in the calculations above. It's the opposite of the relative velocity. But this doesn't help me any. As I showed, using the relative velocity...

I read a while ago that tsunamis are actually classed as shallow water waves (until they hit land). The velocity of shallow water waves is proportional to the square root of the water depth, IIRC. This is why a tsunami travels fast out in the ocean, but slows down when they reach land.

rcgldr, thanks for your help. But I've spent the last few days reading through books and checking out some code and am no closer to understanding this. And it seems another member you've helped in the past is having the same troubles understanding this concept. The thing is, I get how lift...

Ok but the thing is if I zero out the relative side wind component and use the resulting vector in the lift calculations, I can make the aircraft do barrel rolls etc fine. But if I use the entire relative wind vector, weird things happen. Things like the lift force seemingly going negative when...