Recent content by khfrekek1992

Wow! Thank you so much Delphi51, I Like Serena, and ehild! This makes so much sense now, the problem is a lot easier than I thought it would be... (Sorry I wasn't on for so long after I posted the question.) But thank you so much for all the help! That helps so much! :) You guys rock!

Homework Statement Two parallel sheets of conducting metal are very close to each other (A>>d), they have charges of Q1 and Q2 on them. What is the force between these two plates? Homework Equations Gauss' Law The Attempt at a Solution From what I understand, you can use Gauss'...

This seems like such an easy problem but I have no idea where to start..

Or am I doing this wrong?

Homework Statement Two square parallel sheets with area>>distance between them have total charges of Q1 and Q2 on them. What is the force between them? Homework Equations Q1in+Q2in=0 Q1in+Q1out=Q1 Q2in+Q2out=Q2 Q1out=Q2out The Attempt at a Solution I set up 4 equations for the...

Ah! I got it now :) Thank you so much for your help! I appreciate it soo much! :)

Oh! I see how you get that now.. Thanks so much! That helps a ton :D

anyone? :)

Oh! I get it, so and using the product rule - I get it to equal L^2*B_0[a*exp(-a*t)*cos(w*t)-(a-exp(-a*t)*w*sin(w*t)], right? So in this case, w (omega) is the angular velocity of the system?

Ohhh okay I understand what I was doing wrong, and another thing I'm doing wrong I think, is that the Area isn't actually changing, is it? So dA/dt=0, isn't it the angle that is changing? d(theta)/dt? So (with product rule this time)...

I am so lost.. :(

so theta is moved over by d(theta) shifting over r-hat and theta-hat.. What would d(r-hat)/d(theta) be?

Okay, so doing that I got flux=B*A*cos(theta)=B*A*cos((omega)t), and EMF is -d/dt(flux) so I get EMF=(dB/dt)*A*(omega)*sin((omega)t), then differentiating B gives EMF=a*omega*B_0*l^2*sin((omega)t)*exp(-a*t). But that wouldn't make sense, would it? Because I just used l^2 as A, which should be...

Yes, the flux through the loop creates a torque on the two ends of the loop making it rotate, thus making the Area vector change

Oh! oops I totally forgot, the magnetic field is in the z-hat direction, and the loop rotates around the x-axis, so when theta=pi/2, the loop is parallel to the field, making its area vector perpendicular, and vice versa for pi