Recent content by Copycat91

I have a blog that contains some physics problems and solutions. I think its good to improve your physics skill. Also, I have a download link to some IPhO problems on the same blog. Here is the link of my blog: http://collectionofphysicsproblems.blogspot.com" I hope it would be useful.

I have a blog that contains some physics problems. I think its good to prepare yourself for olympiad. Here is the link: http://collectionofphysicsproblems.blogspot.com/" Maybe this can help you.

Yes, it is. In the middle of earth, no acceleration, but we still have velocity. You can use gravitational acceleration inside of earth: [TAB]g'=GMr/R^3 where r is distance from center of earth, R is Earth's radius, and M is Earth's mass. It's just like a simple harmonic oscillation.

Hmm... Wouldn't it really need integral? If I use archimedes buoyancy force, it would... W=integral(ρgV dh)

Homework Statement A solid ball with radius r and mass m is located inside an opened wide tank filled with water. The ball has the same density with water. http://3.bp.blogspot.com/_jn57XA2jLxY/SXnPszTUVsI/AAAAAAAAAEY/e1K41pJXdRc/s1600-h/Get+Ball+Out+from+Water.jpg" Calculate work required...

Apply Coulomb's law for each charge separately. Then use vector superposition once you find electric field for each charge.

Can we consider the initial condition only? There's also gravitational force and air friction on both balls. It's hard to imagine...

The thrown ball, because it has initial velocity, and the other ball doesn't. How's my answer?

Homework Statement Two identical small balls are shown in picture above. A ball is thrown from the ground and another ball is dropped without any initial velocity. First, consider no air friction. In order to make the balls collide each other, the ball on ground has to make an angle α from...