Recent content by yoamocuy

Hello, I'm wondering if it is possible to calculate current the collector current of a phototransistor that is paired with an IR Led? I have an IR Led that is 13.6 cm away from the phototransistor and has a radiant intensity of between 65 mw/sr and 125 mw/sr. The phototransistor that I'm...

Oh I got it now

I've combined the two equations to get: (A-j*2*A*f*∏)/(1+4*f2*∏2) but it doesn't seem that the denominator can be factored at all. I can factor the numerator to get A*(1-j*2*f*∏)/(1+4*f2*∏2) but that doesn't seem to help me much yet.

Ok so I realize these are the same answer, but how do I simplify complex numbers like the one I got in my answer? I've been trying to multiply it by the complex conjugate but haven't been getting much luck :/

Homework Statement I need to find the Fourier transform of v(t)=A*e(-t) such that t≥0. Homework Equations ∫v(t)*e(-j*2*∏*f*t)dt,t,0,∞) The Attempt at a Solution ∫v(t)*e(-j*2*∏*f*t)dt,t,0,∞)=A/(4*f2*∏2+1)-i*(2*A*f*∏)/(4*f2*∏2+1) the answer should be A/(1+i*2*∏*f). It seems...

I've been looking into the induction heating a bit lately and have come up with a few questions. One is in regards to hysteresis losses. I know what hysteresis is and how it contributes to the heat generation, but how much of an effect does it actually have? Some articles I've read have...

Homework Statement A point charge of 20 nC is located at (4,-1,-3), and a uniform line charge of -25nC/m lies along the intersection of the planes x=-4 and z=6. (a) Calculate D at (3,1,0). (b) How much electric flux leaves the surface of a sphere of radius 5, centered at the origin? (C) Repeat...

Isn't that what I did above? I didn't originally show the ax, ay, az in my work but I just added them in there for clarity.

Homework Statement A field is given in spherical coordinates as F=[cos(θ)/r2]∙ar+[sin(θ)/r]∙aθ. Express F in terms of x, y, z, ax, ay, azHomework Equations ar∙ax=sin(θ)cos(∅) ar∙ay=sin(θ)sin(∅) ar∙az=cos(θ) aθ∙ax=cos(θ)cos(∅) aθ∙ay=cos(θ)sin(∅) aθ∙az=-sin(θ) x=r*sin(θ)*cos(∅)...

Homework Statement I'm supposed to design and build the intermediate frequency amplifier portion of an am receiver. Homework Equations The Attempt at a Solution I've been looking around online and correct me if I'm wrong but the intermediate frequency amplifier takes an ac signal, filters...

Nvm, I figured out what's going on in the different charts. Everything's good now.

Hello, I'm trying to find a metal that has a conductivity that's about 150% that of stainless steel grade 384. I've been looking for some charts that compare conductivities of metals but all the charts I find seem to have a few discrepancies. Could someone give me a link to a reliable chart...

well 45 at 0 degrees is still given in the s domain. 45 will be the magnitude and 0 will be the degree that's in the cos or sin if you have a jw anywhere, but since I don't have any imaginary numbers in my s then I shouldn't have a cos or sin anywhere. My problem is, I can solve for my poles...

O i accidentally forgot to multiply my 25 by s at the beginning. I actually end up w Vc/Vin=9/(s^2+10s+9) so that makes my poles s=-1,-9 and my zeroes still + or - infinity.

Homework Statement everything's in the picture. Homework Equations V=I*R Ic=Iin*R/(R+C) The Attempt at a Solution Ok, I think I got the first part alright. I found the current in terms of Vin to be: Vin/(25+(22.5*225/s)/(22.5+225/s)) which simplifies to Vin*(s+10)/(225s+475)...