Recent content by squiffy

Hi, I posted this question a while back on these forums. Didn't get an answer though. How long will it take for two identical masses to reach each other by their attractive gravitational force? Their masses can be 1kg and the distance between them 1m to simplify it. Do NOT assume that the...

Well, I gave the problem to my physics teacher. He solved it by considering the kinetic energy at the start and end of the system. It gave a value of about 37 hours. I tried it by assuming the rate of change of acceleration was a constant, which gave an alright approximation (24.05 hrs)...

I'm not exactly sure what you mean here. Do you understand what the Planck time is? It's the smallest amount of time (quanta of time) that is meaningful. Measuring times shorter than that are meaningless. On a second look, I have a vague idea of what you mean. Correct me if I'm wrong, but I...

I don't think so. You can keep piling more and more energy into a system and it will raise its temperature further and further. There is a theoretical lower limit on temperature though. That is absolute zero, when no particles move at all. I was going to mention phonons here too, but are...

Hmm, on second thoughts what I've done is completely wrong. When I integrated this: a = \frac{G}{{(1 - 2d)^2 }} I accidently assumed that d was constant, which it isn't. It's a function of t, so it has to be integrated itself. So the big problem is finding d in terms of t. Any ideas?

Ok, let me show you what I did before posting here. F = \frac{{Gm_1 m_2 }}{{r^2 }} But m_1 = 1, m_2 = 1 and F = ma So: a = \frac{G}{{r^2 }} Now, r is the distance between the two masses, so taking the initial position of the first mass as the origin, r can be expressed as: r = d_2 -...

Hi, all. I have a problem I wish to solve. It's not from a textbook, I thought of it myself. If two masses of 1 kilogram each are 1 metre apart in space, how long will it take for them to reach each other from their attractive gravitational forces? Remember that the force (and hence the...