Recent content by robgb

I have a quantum physics 2nd year undergraduate exam in a few weeks, I'm a complete beginner to Fourier series, can anyone help explain how to answer this question please? Thanks, rob. The question is http://mobilecrazy.net/fourier.jpg

Thanks mate, yep i essentially understand, just 1 question though: How did you get from the second line to the third line in the following: \begin{equation*} \begin{split} \int_{-T/2}^{T/2} f(t) \sin{n \omega t}\ dt &= \int_{-T/2}^{T/2} \left[ \sum_{n=1}^\infty b_n \sin{n \omega t}...

The Fourier Series! Hi guys, I'm having a bit a trouble helping my daughter with this question on the Fourier series approximation: The Fourier series for a real, odd function, f(t) can be written as: f(t) = [SUM to infinity, n=1, of]: b[subscipt n] sin(nwt) where f(t=T)=f(t) and...

Thanks Jess. Could you shed any light onto c & d? Any chance anyone came come up with an answer? These are questions my son have been set, and I'm trying to get some answers so that I can help him with them. Rob.

Thanks again Jess! lol I think I'm having a bad day! I've made the corrections. I'm guessing the answer to a) would be that is is a quasistatic process due to the pressures being allowed to equalise. But are there any better reasons for this? Rob

Hey Jess, sorry about that! I was just in the process of changing the question! Thanks for you help, I think I have that one sussed now though cheers. Any chance you can have a go at this one? Rob.

Halls of Ivy - I think you missed out the spuare root in my equation when differentiating. Any chance you could show me the working again with the square root in there? ie the differentiation etc. many thanks!

Thanks guys. Sorry, I left a few points out... I need to evaluate the taylor series of that equation to second order about x=0. Then I need to compare f(0.1) with my taylor series approximation. Does that make it simpler? Thanks a lot for your help.

Can anyone please help with the following questions?... Two gas cylinders A and B for which Va = 30 litres and Vb = 10 litres are linked by a narrow pipe containing a valve. Initially the valve is closed and cylinder A is charged with an idea monotomic gas to a pressure Pa = 10Ma at Ta =...

I've corrected the values of alpha and beta, does it make more sense now? I've been told that this question has all the information you need to solve it. Can anyone help? Thanks, rob.

Ok, thanks guys. I'm still unsure as to where to go from here. Any chance of a worked example anyone? Please! Thanks, rob.

means nothing to me sorry, could u be a bit more specific? Thanks.

Thermal physics question... A wire resistance thermometer is constructed with material that has a resistance that varies as temperature as below. R=R0 (1+ alphaT + betaT^2) where constants alpha and beta are 3.8 x 10^-3 k^-1 and -3.0 x 10^-6 k^-2 respectively. Calculate the...

Hi, Yes, in the question it didn't actually mention the temperature, just that it was the triple point. Its supposed to be a pretty basic thermal physics question, any ideas what formula I would need to use? Thanks, rob.

basic taylor expansion... Hi, could some one explain how i could use the taylor series to expand out: f(x)= 1/sqrt(1-x^2) Any help would be appreciated, thanks.