# Search results

1. ### What branch of mathematics to study to understand Quantum Mechanics?

Sorry for the very late reply, but thanks a lot guys!! Linear Algebra, calculus, and DEs amazing!! I'm trying to learn QM for practical applications, mostly for energy and propulsion applications. Atm, I'm working out solutions for energy use and I keep getting defeated by classical...
2. ### What do you call this kind of attraction?

-You get two pieces of dry glass material with perfectly flat faces. -You press and rub them together. Initially, they seem to glide smoothly against each other... -...Eventually, after a few strokes, friction force gets very strong until the point you can't rub them at all. -A this stage...
3. ### Rate of displacement of individual gas molecule help

Thank you, well, I don't actually need a 'precise' value of the mean. If you're saying that diffusion gives a good approximation of the speed, then that is good enough for me.
4. ### Rate of displacement of individual gas molecule help

Has anyone made a calculation for example, how much (or the mean) time it takes for an individual gas molecule to be displaced a distance of one meter (measured straight) from its original location? For example, air molecule at ambient pressure with a mean free path of 68 nm. That would be...
5. ### What branch of mathematics to study to understand Quantum Mechanics?

I just got a book on Quantum Mechanics, but at a loss with the maths. I had Algebra, Trigo, Calculus, differential equations, etc, but that was a long time ago, now as a programmer, I hardly ever think of those and forgotten them as a result. I believe I still have strong enough concept of...
6. ### Java Sample code/tutorial for simple, educational, physics java applets?

Fantastic m8! For the first time I'm seeing the applet codes! Appreciate it!:wink:
7. ### If sound travels faster through solids then why can't we hear through doors?

If you can't hear sounds behind closed door in a sealed room: - Your parents gave you a sound-proof room with a sound-proof door or; - You have hearing problems (genetic, war veteran, music nut, etc) I sure can hear people say things about me behind closed doors even if they're whispering!
8. ### Java Sample code/tutorial for simple, educational, physics java applets?

Something like this: http://www.falstad.com/vector/ Particularly concerned with particle motions. I don't know how to begin with using physics equations for creating simple java visual simulations. Can be 2D or 3D. I know some java programming so I'd prefer code examples than...
9. ### Why does a rock shatter a glass, but a bullet pass through.

Probably the first correct answer, I agree. My answer would be if it's a rock, the glass tries to fight so ends up shattering whole. If it's a bullet, glass knows it has no chance, raises the white flag and makes a neat 'lil hole to let bullet pass. It's like guy trying to fight a mugger...
10. ### Maxwell's Demon via molecular reed valves can produce work?

Well not literally The Maxwell's Demon... If a one-way reed valve can be brought down to size of only a few molecules, don't you think it could allow passage of a gas molecule across a barrier in one direction only? How I think it could work: -The small size (molecular) of the valve is...
11. ### Does colder intake charge really work on Dyno?

Thanks Edge. I'll guess I did the right thing. I thought I'm just saving money. I've basically left the intake tract factory stock but wrapped them in insulating tape, used paper intake manifold gasket and bypassed throttle body coolant. I've also rerouted the inlet to a ram scoop I've...
12. ### Does colder intake charge really work on Dyno?

Hello, I got a question on auto engines. especially on Naturally Aspirated engines. I know that colder intake = more oxygen in the mixture, then the ecu will compensate that with more fuel, etc, etc, more power... But colder air will also result to less efficient atomization of fuel...
13. ### Can I use 24 Volts input to a car ignition coil?

Thanks for your responses so I guess it will likely work. I think I might make a heat sink fan for it. Pulses will be in the micro second range with much larger duration of 'no current' in between. I've once run several high energy pulses before in an open coil with pvc insulation. Really...
14. ### Can I use 24 Volts input to a car ignition coil?

I'm feeding the current in pulses via 50v 6800 mfd capacitor. Will it destroy the ignition coil instantly, or will just overheat it? It won't be for automotive use but for general high voltage experiments. As long as instant destruction is a remote possibility, it's easy enough to mitigate...
15. ### Does engine RPM affect gas mileage?

I drive a '97 Toyota Starlet automatic(with a home-brewed cold air intake, anyway..). Even though it's automatic, you are actually still much in control of engine rpms by how you use the throttle and switching overdrive on/off. I drive to and from school a total of 40 miles a day and here's...
16. ### What is the speed of current

You can calculate it, I just forgot how! If memory serves me right, it's usually few centimeters per second for normal current densities. It will take an incredibly high amount of current and/or very fine strand of conductor to take the drift up to relativistic speeds - if only there's such...
17. ### Is fire matter?

Hydrogen fire is plasma.
18. ### SF Writer in need of assistance - SPACESHIP FUEL

It's actually quite common in SF literature. For example, in Star Trek, they have managed to weaponize the know-how of vacuum energy into the 'quantum torpedo'. Also in Star Trek, the Romulan race, uses miniature but stabilized black holes held by a certain field to power their starships...
19. ### SF Writer in need of assistance - SPACESHIP FUEL

If the starship is fully electrical powered (not needing fuel to fly around), we could have an extremely high capacitance capacitor as its energy storage. It would be recharged at the docking port using solar power. This high energy capacitor will be using molecules itself as its capacitor...
20. ### Does light exerts force?

Or high energy radiation like X-rays and Gamma rays.
21. ### Why don't we emit radio waves

Because it could trigger painful sparks every now and then so no, thank you.
22. ### What happens to the energy in case of destructive interference ?

Acoustic padding convert sound to heat but they are very porous so they are ill-suited for outdoor use. Large scale use will also make them extreme fire hazard.
23. ### Is this possible?

Since I'm rated amateur, I do the reverse. I experiment with the object first, then I do the math, makes me easier to understand the math involved! It's also gives me that 'creative spark' if I do that in that order. Sometimes the spark causes fire though. That worked for me except that I...
24. ### Bose Supernova

Most likely, it's just an analog. Similar analogs have been done recently like analog of a black hole event horizon using sound, etc. Doesn't really happen like full size things just looks and behaves similar.
25. ### Light damages buildings?

Flash photography could reveal hidden cameras around buildings if there are any or even possibly damage their sensors.
26. ### Using magnets to reach near absolute zero?

Yep, that was a quickly thought up idea. Actually, only the compression front of the wave, will be strongly affected by a repelling magnetic field. The magnetic field would be turned off before the compression front would bounce in the opposite direction. So that would only serve to dampen...
27. ### Using magnets to reach near absolute zero?

There you go, the random kinetic nature of particles won't get you anywhere! However, it may be possible to introduce some order into the system by using sound synchronized with pulsing magnetic fields tuned to the sound frequency in such a way to keep slowing the molecules down at each passing...
28. ### Using magnets to reach near absolute zero?

Most likely, it won't work. You can't hold a proton motionless with magnetism. They have to be moving in order to be affected by magnetism, unless protons exhibit magnetism at zero velocity. Only electric fields (static electricity) can effectively affect their motion at very slow speeds, but...
29. ### Where is gravitational energy stored?

Are you speaking of mass or weight? If you separate two objects that are attracted to each other, the energy used is transformed to potential energy. This potential energy is released if the thing that's holding apart the two objects that are attracted to each other is removed. Upon release...