Recent content by Scottpm

Often it helps to draw a picture of the problem. Then represent forces on any objects as arrows as the are vectors. You can do the same with accelerations and velocities, just make sure you don't confuse the different vectors.

While others have answered this, I thought I'd throw my 2 cents in (or is it 25 cents now with inflation?). It is perfectly fine to have different coordinate systems for two (or more parts) of a problem. I like to think of it this way: I hate it when the two ends of the string (even...

The four fundamental forces are electromagnetic, gravity, weak interaction, and strong interaction. Electrostatic is just a special case of electromagnetic.

Hello, I am a physicist and earned my PhD back in 1994. I put myself through grad school by teaching (for the university) and tutoring (as a side job). I've worked in a national lab for the last 13 years with summer interns for about 10 of those years. I find that I have missed teaching and...

Let's simplify this a bit to better understand it. Consider your hand as it pushes a block across a horizontal surface. Why doesn't your hand go through the block? Your hand is made up of molecules, which are made up of atoms. Virtually all the mass of an atom is in the nucleus, which is so...