Recent content by locke

Sorry to keep posting questions here, but I'm a little confused. Surely if a vibration is closer to the natural frequency of a solid, the greater the sound transmitted through the solid (rather than absorbed by it). These questions are getting disorganised, to summarise: -is sound of frequency...

I'm trying to figure out what the probability of two people in a room sharing a birthday is, if there are 19 people in the room. Originally i assumed that the chances of any pair of people sharing a birthday are 1/365. Since there are 19c2 pairs of people in the room in question, I thought...

I always assumed that we could detect transmitted sound on the far side of a barrier because the incident sound waves vibrate the barrier. In light of what you have told me, I'm obviously mistaken. My next question then is how are we able to hear something on the far side of a wall? Can...

Seems sensible. But why is it that low-frequencey sound is absorbed less by the ground (to take an example of an object with larger dimensions) than higher frequencies? Thought: When a pressure wave impacts the surface of a wall, I would imagine this sets up a vibration that travels though...

I would like to know the physics behind the low attenuation and low absorption of low frequencey sound. Every book/resource I've consulted so far presents these two propeties as empirical facts without really seting them in any kind of theoretical framework. Can anyone here point me in the right...

Waitaminute, it's obviously in phase with I. Currents induce magnetic fields, not voltages. Sorry guys, think it's past my bedtime...

Imagine I take a pair of helmholtz coils and apply a DC current, modulated by a much smaller AC current so that the B-field between the coils varies sinusoidally about some fixed value. Will the AC component of B be in phase with the AC voltage, or the AC current?

I'm trying to track down a quantitative proof that the most uniform magnetic field between two Helmholtz coils occurs for a separation equal to their radii. So far I've just been playing around with the Biot-Savart law and proving that B is identical at several trial points along the axis...

No need to worry, I'm familar with basic quantum phenomena. If such a thing exists...

*penny drops* Thanks, that's exactly what I wanted to know.

I'd imagine that definition was only intended to apply to straight lines.

If someone says "frequency" to me, I understand it be the number of periodic events happening in a unit time. Perhaps my question should be: "Does a photon exhibit any kind of periodic behaviour?"

What your friend was probably talking about was that the nulceus is too small to contain an electron from a quantum perspective. A nucleus is an extremely tiny thing (diameter aprox 10^18cm), and if there was an electron inside it then we would know its location almost exactly. According to...

Uncertainty principle would forbid this from happening. If you had some way of knowing the particles had 0 seperation, they would then need infinite momentum.

So...If you say a photon has frequency x, it just means that if you took a whole pile of these photons and put them together you would get monochromatic light of frequency x? Does this mean then, that the concept of frequency exists only in the abstract for a photon by itself?