Recent content by Teegvin

Did the teacher say the thing was a battery? If yes, then I have no idea what happened. If no, and you assumed it was a battery, your assumption was probably wrong, and there are actually two different objects. The first is simply a piece of metal, and fell through the tube unhindered. The...

Do you know the parallel axis theorem? The moment of inertia for an object rotating about an axis that does not pass through its centre of mass, but which is parallel to it, is mr^2 + (moment of inertia about an axis through the centre of mass and parallel to the other axis) The r is the...

I don't have anything to contribute myself, but I read a nice talk by Richard Hamming a few weeks ago called 'You and Your Research' which I think is somewhat relevant to the thread. It's a bit long, but I'm sure at least some of you will enjoy it. He talks about why some people do great...

I think he means that the complex numbers are closed, unlike the sets within the complex numbers.

That is, what distinguishes dinosaurs from other reptiles that existed at the same time, or which still exist, such as crocodiles? People do not normally consider the crocodiles to be dinosaurs, despite the fact that they appeared before many other reptiles which have since gone extinct and...

It would go back to the positive-x because it is a side-ways parabola, x=(y+4)^2.

It will continue to radiate until it reaches equilibrium with whatever radiation is hitting it. After that it still loses energy, but it gains energy at the same rate.

Yes, the potential energy of the gas at the outside decreases. When the cloud is spread out, the gas closer to the outside has more gravitational potential energy with respect to the centre than it does when it is dense. The change in potential energy in going from spread out to dense is...

The energy comes from the gravitational potential of the gas. There is no energy created or destroyed. Where's the conflict?

Does a loud noise that is beyond my range of hearing still do damage to my ears?

The boat displaces a weight of water equal to its own weight. The left side of that equation is equal to the weight of the boat. Weight of bottom + [total volume of the sides(2h(L+W))][density of the steel][g] The right side is the weight of the water displaced by the boat, which is the...

Good solutions. I especially like DaveC426913's. Good question about the ropes. The ropes are cemented into the ceiling as well. Sorry I neglected to mention it. :wink:

This is good advice. Thank you :cool: The other problems were less trivial. That was the easiest problem there, and the most likely person to be doing would be someone in grade 10.

Yes, of course! I left that out. Thanks :wink:

You are locked in a 50'x50'x50' room which is on 100' stilts. There is a small window near the floor on one side (too far from the stilts to reach), with a small hook embedded in the floor beside it. In the centre of the room hanging from the ceiling are two 50' ropes. You have no tools...