Recent content by Vector Sum

Don't forget the Rams. They moved to California in the 40s just when they were getting good.

Yet you still need the mass of the projectile to know total energy. If the mass is not given, you can provide the answer as a number "times m." But, I'm guessing that perhaps the mass could have been determined from the first part(s) of the question?

Vector Sum: Big Boy American (Northeast), with Immigrant mother (Britain) and Canadian Father

The movie is funnier for anyone who has ever been in a band, or at least knew people in a band. "Christmas with the devil" was a big college radio hit, and one of them (not Harry Shearer or Chris Guest, the other one) was part of the the Canadian version of a "Feed the world" type...

D'oh! I knew that. My bad. And it was right in HallsofIvy's post. Yes, phase angle is the "phi" after the wt, and it does give the "starting point" so to speak, of the oscillation. Phase difference is just that: the difference, in radians, between two angles. Could be the difference...

The formula A cos wt gives you the displacement from equilibrium. the w (omega, really) is the phase angle.

Is this your first year of undergrad? I hope not, because I think second year was the worst! If you get past these years, the sheer volume tends to drop. Also (I wish I had gotten this info when I was in college) Don't feel bad about joining the 5-year club! No one cares if it took you...

Thanks all. I've already jumped in. God knows why! It's my job to teach physics, and I answer questions all day, so what do I do with my free time? Answer more questions? It's an odd compulsion isn't it? Sort of a "MUST ... FIX ... WORLD " complex.

I see the same problem that Galileo sees: The question ought to be "what current will hold the cross-piece at .05 m." For this you just need to balance two equations, one for the force of gravity, and one for the Lorenz force (that's the "BIL" formula). Solve for I. Accoring to "B =...

You are sort of correct by say "diffraction is less," if you mean that the beam is less spread out. If the slit is widened, the path of the photons would become less uncertain, meaning the photon concentration that falls on the central maxima will be greater. This means greater intensity.

Well you have rev/sec. How much distance will an object go in one rev? When you figure that out, you can find the "tangential" speed in m/s, and then your formula might make more sense.

THis is a great problem, but maybe not for the students! Centripetal force must be provided by some other recognizable force. In this case, it is provided by the horizontal componant of the tension. The vertical componant of the tension has to balance the only other force on the chair...

Remember, when traveling in Europe, you usually don't stop to see the dirty and dangerous places. When you travel to America, most people go directly to the dirtiest and most dangerous cities ( or they go to the Grand Canyon etc.). If Europeans came over to visit Boulder , or Portland (either...

Try here: http://www.creative-science.org.uk/windmill1.html This si for a large windmill, but you can size it down and use stiff paper (like a manilla folder). It's easy to do, take about an hour.