Recent content by MrNerd

I had forgotten about that. In that case, I'm pretty sure magnetic permeability interferes with the magnetic field. I think it draws the magnetic field lines into it or something. Wikipedia also has something on the Meissner effect, but I doubt superconductors are going to be used in a school...

That's a fairly simple problem to solve. I believe a faraday cage is what is used to screen electric and some electromagnetic radiation(depending on the size of the holes used in the screen). Basically, it's just a metal cage with small holes.

I think my username is pretty self-explanatory.

What is achievement without the pride to go with it? Reasonable pride, of course, not the pride where you act like an arrogant prick. Good job with your music.

You'll probably need a small capacitor bank to power your magnets(presumably electromagnets). Basically, this is just a bunch of capacitors wired in series and parallel to store energy, and release it in a pulse, resulting in a higher amount of power at the same energy. Please note that...

Yes, but it doesn't do much if everyone disagrees with the unhappy person. If everyone is super obsessed with the football program or something, and a minority are in the screw football mentality, it won't do much.

This guy is ingenious! I would have never thought of that. I suppose people back then had a fair amount of time to think after they collected their food and because they lacked reality tv.

In order to pump the air into the tank, the pressure from the pump must exceed the pressure from the water. If you want a truly accurate answer, you may need some basic calculus as the pressure from the water at different levels of height in the umbrella will change slightly. It won't be much...

Hmmm...I would have sworn that microphones already did this. The vibrations from the sound waves created a small current or something along those lines. I think it was something about the vibrations causing a tiny magnet to vibrate in a coil of wire, inducing a voltage/current.

Infrared(I think that's what you mean by infarade) waves encompass the region of the electromagnetic spectrum right before light, commonly considered as heat radiation. As it is present right before light, it has a frequency that is a bit lower, and a wavelength that is higher as a result of...

Well, I can't say too much about it, but I can give some ideas. It probably involves the laws of physics and the equations that result from them. Things like ballistic projectiles typically covered in a high school physics class and work/energy. You could probably make a very basic physics...

I was fairly sure that Newton's Third Law always held true, never hearing of it not holding true. In electromagnetic things, it's fairly simple. Think of it this way: Particle A has a charge of +1C. Particle B has a charge of +2C. The force is given by F = \frac{kQ_{1}Q_{2}}{r^{2}} This...

It'll take a bit more to calculate the force than simply the weight and speed. The helmet absorbs some of the impact, and passes the rest onto you. If an object is speeding relative to an observer, it has kinetic energy defined as (1/2)mv^2, at nonrelativistic speeds, which are basically...

Alright, inside it shall be then!

If the horse does not move up or down, then it has a net force of 0. This means that the gravitational and normal force cancel each other out. As a result, the only net force acting on the child is the centripetal force you found, the 59.9N.