Recent content by nickmai123

I have a question, specifically to physics people, on their definition of the Fourier Transform (and its inverse by proxy). I'm an EE and math person, so I've done a lot of analysis of (real/complex) and work with (signal processing) the transform. In a physics class I'm taking, the professor...

I need some help showing the following limit. I don't really know where to start, and I was just looking for a quick tip or two to begin the proof. Thanks! Problem: \lim_{n\rightarrow\infty} \sqrt[n]{\alpha^n+\beta^n} = max (\alpha,\beta)

Firstly, you ignored the equations section. Please enter the equations you know. Secondly, you didn't put any attempt at a solution. The purpose of PhysicsForums isn't to do your homework for you but rather guide you towards a solution. On top of that, I don't think this question is in the...

Thanks.

I have a quick question about the relationship between the complex Fourier coefficient,\alpha_n and the real Fourier coefficients, a_n and b_n. Given a real-valued function, I could just find the real coefficients and plug them into the relation below, right?Fourier Coefficients for periodic...

Google books prob has the first few chapters of the common DE books (i.e. Brannan & Boyce, Boyce & DiPrimma, Polking & Boggess). Check your school's library. Usually they have most of the old editions of these books. You can go write them down or photocopy, though the latter depends on your...

Homework Statement Using the Schroeder-Bernstein Theorem, prove that any two intervals of real numbers are numerically equivalent. Homework Equations Schroeder-Bernstein Theorem: Let A and B be sets, and suppose that there are injections from A into B and B into A. Then, there exists a...

Homework Statement Find the reflection coefficient for electrons traveling toward a potential change from V to V_0 with a total energy E > V_0. The potential diagram is just a unit step function. It goes from V = 0 to V = V_0 at x=0. In piecewise notation: \begin{displaymath} V(x) =...

Yeah sorta. I knew that I had to do: V_{c} = V_{p}(1-e^{\frac{-t}{RC}}) \frac{dV_{c}}{dt} = \frac{-V_{p}e^{\frac{-t}{RC}}}{RC} Should I just set this equal to the rate of change of the voltage of the input sine wave? I.e.: \frac{dV_{c}}{dt} = \frac{-V_{p}e^{\frac{-t}{RC}}}{RC} = -(2\pi f)...

Sorry, lol. Question: Estimate the time after the peak input voltage when the diode shuts off.

1. The question. Suppose that the input frequency into a full-wave diode bridge rectifier is 60Hz, and suppose that the RC time constant of the network filter capacitor and the load resistance is 10ms. Estimate the time after the peak input voltage when the diode shuts off. The circuit looks...

Yeah I realized that after a few minutes but I didn't edit my post. Also, lol @ the response 3 months later... :-)

I can't help you solve it. However, I will bump it by retyping it with LaTeX for you :-) U\left(x,y\right)=\sum B\sin{\left(\frac{n \pi x}{a}\right)}\sinh{\left(\frac{n\pi(b-y)}{a}\right)}

The force of gravity never reverses direction. It will pull downwards. The centripetal force reverses direction because it will always point towards the center.

It's centripetal force. He's in an inertial frame of reference. The normal force at the top is the SUM of the centripetal force and gravity. Centripetal force is pulling you downwards along with gravity. Thus, the normal force has to be equal the sum of those two. That said, think about what...