Recent content by Rombus

Homework Statement Find the time constant x(t)=4 e^{-4t} u(t) Homework Equations \tau = \frac{1}{\lambda} The Attempt at a Solution \tau = \frac{1}{\lambda}= \frac{1}{4} = .25 I know the unit step is shifting the start of the decay function to zero, but I'm not sure how or...

Yes.

You want to use trig identities to make both sides equal. Cos(2θ) has another form for example.

Thanks for the replies. This makes a lot more sense now. So knowing this I would integrate over the surfaces separately. So it appears it would be easier to integrate in cylindrical form correct? So I would want to change the vector field from rectangular to cylindrical?

Homework Statement Given a vector field A=(2x,-z^2,3xy), find the flux of A through a surface defined by ρ =2, 0<\phi<\pi/2, 0<z<1 Homework Equations ∇\bulletA? The Attempt at a Solution Can I use divergence method here? This is a closed surface correct? A cylindrical...

Is this question in the wrong forum? Any help would be appreciated.

Homework Statement If vector A=(2x,-z^2,3xy), find the flux of A through a surface defined by ρ =2, 0<\phi<\pi/2, 0<z<1 Homework Equations divA? The Attempt at a Solution Can I use divergence here? This is a closed surface correct? Is this is a cylindrical wedge? Also do I need to...

Thank you for the reply. So if my equation is: \bf{Z}ab R_1 + j \omega L_1 + \frac { \omega^2 (k ( \sqrt{L_1 L_2)^2} {R_2 + \frac{1} {j \omega C}} + j \omega L_2)} I solve for k, the coupling coefficient so that the imaginary part of the impedence is zero? Is K' the same as k? Or is K' my...

Homework Statement The coupoing coefficient of K' of a linear transformer is adjusted so that Zab is purely reissitive when ω= 25k rad/s. What is Zab? Homework Equations Not sure The Attempt at a Solution I'm not sure how to being this problem. For one, from what I've been...

of course! Okay, so the angle is zero or 180. So upon finding the dot product how would I determine the angle between these two fields from the result of this dot product? (2 Sin(θ))/r + (Cos(θ) Sin(2 θ))/r Do I just plug in zero for theta?

Hello, thanks for the reply. I blame lack of sleep on my dot product equation mishap. :zzz: So, the angle between the vector fields is 90 degrees and the dot product would be 0 correct?

Homework Statement Show that the vector fields A = ar(sin2θ)/r2+2aθ(sinθ)/r2 and B = rcosθar+raθ are everywhere parallel to each other. Homework Equations \mathbf{A} \cdot \mathbf{B} = |\mathbf{A}||\mathbf{B}|\cos(0) The Attempt at a Solution So, if the dot product equals 1. They should be...

Ok, thank you, and thanks for the tip about posting.

So after fixing that mistake is this the equation I'm looking for? Thanks again.

Thanks for the replies. Is this the equation I'm looking for? 154910[/ATTACH]"] edit: looks like I lost my y^2 along the way.