Recent content by 012983

I suppose you're right. Although I completely forgot that F = ma = p/t... for the longest time I simply had p = mv in my head. I'll do some digging around tonight and see if there is some accepted "estimate." @McQueen: Haha I guess so. At the end of the article they mentioned someone going to...

By time of impact, do you mean duration of impact? Since we're dealing with concrete, I assume that the impact is near instantaneous, right? So t could feasibly be, say, one millisecond? So since F = ma = p/t, p = ma*t or 980 N * 0.001 s = 0.98 kg*m/s? I also still don't know what killed...

Recently I read an article in the newspaper (yes, someone still reads them) of someone who committed suicide by jumping out a window of a 7 story building. That got me to wondering how much "force" he experienced at the moment of impact. (I don't know if force is the metric I'm looking for...

Homework Statement A conductor in the shape of a square of edge length 0.28 m carries a current I = 17.0A. Calculate the magnitude of the magnetic field at the center of the square. Round your answer to three significant figures. Take the permeability of free space to be 4*pi*10^-7...

Argh, crap. Thank you very much!

So tau = (R2)*(C1+C2), correct?

Oops, guess I messed it up in the edit. So during time t1, q = {C_e}\epsilon(1 - e^{\frac{-t}{\tau}}). Is my understanding of how the capacitors discharge through R2 correct? Or have I got to change the value for my time constant for the second part of the function? Many thanks.

OK, that makes sense. Since C1 = C2 = Ceq, the equation during time t1 when S1 is closed and S2 is open is now {\frac{{(C1*C2)}/{(C1 + C2)}}\epsilon(1 - e^{\frac{-t_1}{\tau}}). Have I made the connection properly? Or am I still missing it?

Homework Statement All capacitors of the open circuit shown below are discharged when, at time t=0, the switch S1 is closed. At some point later, at time t = t1, the switch S2 is also closed. What is the charge Q2(t2) on the capacitor C2 at time t = t2 > t1...

If the electric field at P is equal to (-4*ke*q)/(3a^2), where ke = 8.99 * 10^9, do I proceed by plugging in -8q for q and setting equal to 0? If so, how would I solve for a? a could be any number so long as the numerator is 0.

Homework Statement Three charges of equal magnitude q reside at the corners of an equilateral triangle of side length a. The topmost charge is positive while the charges at the bottom left and bottom right of the triangle are negative. If point P is midway between the negative charges, at...

Yeah, I wasn't too sure about what I was reading in my textbook versus what I was reading on here. My book does indeed do it det(\lambdaI - A)... I assumed it didn't matter if it was det(\lambdaI - A) or et(A - \lambdaI). My mistake. Thank you for your help!

Yeah, I figured it out... was pretty simple to me once I looked at it differently. Meanwhile, though, I'm stuck on a 3x3... I've redone it four times to no avail. [3 2 -3] [-3 -4 9] [-1 -2 5] [(\lambda-3) 2 -3] [-3 (\lambda+4) 9] [-1 -2 (\lambda-5)] Using row...

Ah, nevermind. I figured it out now, thanks.

Homework Statement Given the matrix 3 2 1 0 0 2 0 2 0 Find the characteristic equation and the eigenvalues. Homework Equations |\lambdaI-A| The Attempt at a Solution If the characteristic polynomial is (\lambda-3) 2 1 0 (\lambda-0) 2 0...