Recent content by alexsylvanus

Sorry if x is negative

Does the log property a*log(x)=log(x^a) still hold if a is even and x I imagine that ln(-1)+ln(-1) can't equal zero, even by some mysterious magic involving complex numbers.

This project is really more of just an attempt at a design, not actually building the system, at least not now. I'm still just in high school physics, and I was just trying to apply what I've learned about magnetic fields and current to something practical in the real world. I'm sorry that I...

Thank you!

You don't connect the phone directly to the wall socket, you plug the USB into a box which I assume has a DC output and an AC input. Is this correct?

They're right actually, I wasn't thinking and I just googled "iPhone 4 charger voltage" and I just found somewhere that the CHARGER could take 240v, but I can't find the voltage that the phone can take anywhere.

The coil

Oh yeah, thank you. And I haven't tested the output voltage yet, but I don't think it'll be greater than 240V, which is what my phone is specified to take.

Hey, I hope I don't bother any of the serious electrical engineers, but I was wondering if anybody could help me with a project I'm working on. I want to build a generator that I can attach to my stationary bike that will charge my phone. It has a very simple design, two permanent magnets that...

AP Physics student here, I'm working on a problem that takes into account air resistance, where something is thrown up at initial velocity v_0, and the drag force is proportional to the velocity, so, \vec{F_{drag}}=-k\vec{v}. Using Newtons second law and making up positive, down negative, you...

I'm just graduating High School and thinking about going into Electrical Engineering. Is college science extremely difficult right from the start? Or is there some overlap with high school AP physics/AP chemistry and review period. I've always been really good at math and science, and my teacher...