# Search results

1. ### Drum question

Hello, Is it possible to 'convert' the sound of a drum to a keyboard instrument, e.g. using signal processing techniques. Measure the pitch of a snare drum, and attempt to recreate it in MATLAB? I don't think it's possible, since a (snare) drum doesn't have a fundamental frequency, does...
2. ### Help me with math

Not really in 2unit mathematics, more so in 3unit and 4unit maths. I should've taken them, but my ego wasnt really good!
3. ### Help me with math

Is this the same as 'Discrete Mathematics'? http://www.maths.usyd.edu.au/u/UG/JM/MATH1004/Resources.html
4. ### Help me with math

Hi I am a third year electrical engineering undergraduate, who would also like to engage in higher study of mathematics. I am in awe of mathematics, having done linear algebra and calculus as part of engineering, plus whatever is necessary for elec engineering (Laplace, DE's, Fourier, complex...
5. ### Linear programming problem

Homework Statement Question (to be solved graphically) ------- A coffee company sells coffee under a "Best blend" label and an "Economy blend" label. Both are blended from three basic grades of coffee: Best blend = 40% A + 40% B + 20 % C Economy = 20% A + 40% B + 40% C The market...
6. ### Electric Displacement Field

Can someone please post a problem/situation outlining the motivation / usefulness of the electric displacement field? (Particularly with a capacitor) I'm having trouble understanding the concept and information is sparse on the internet.
7. ### Density of States Confusion

Why do electron states split into bands in solids if states exist for electrons that have the same energy level
8. ### Density of States Confusion

"the density of states (DOS) of a system describes the number of states at each energy level that are available to be occupied. " But I thought there can't be more than 1 electron in a state? How does DoS have any meaning when dealing with eleectrons?
9. ### Continuous time convolution

THat's the thing, when I put it into the integral I have to work out a bunch of inequalities that really makes my head spin. This question is so much harder than the example :(
10. ### Continuous time convolution

Unit step function
11. ### Continuous time convolution

Hey guys, I'm having trouble doing ct convolution i'm trying to convolve two signals together ie, the input x(t) and the impulse response h(t). basically, knowing the impulse response of an LTI system, you can find out the response y(t) to any arbitrary input x(t) using the convolution...

image

First one.
14. ### Optics question

yeah, I'm having trouble figuring out how I can get that very small airy disc size to correspond to resolution on the Earth's surface, 100km's away. I tried using this where di is distance to the image from the lens, and do is distance to the object. But, then I get a very small number and if i...
15. ### Optics question

So I'm looking for a dimensionless number? Not sure what it could be, i'm only given lens diamater, focal length and wavelength.
16. ### Optics question

Yeah, how do I figure out the res on the Earth? I know the Focal length and orbital height. I was thinking you could just multiply the airy disk size by 100000 for 100km
17. ### Optics question

If I have a camera orbiting in space way above the Earth, and it has a diffraction limited resolution of 4.1*10^-7 m (diameter of airy disc), then how can I find out the corresponding value if the lens is supposed to take images of the Earth?
18. ### Polarization question

Hi all.. I don't understand polarisation. When unpolarised light is passed through a polarizer, the result is linearly polarised light with the E field oscillating in a direction parallel to the transmission axis of the polarizer. Say it passes through another sheet (analyzer) with its...
19. ### Capacitor discharge problem

So, in between the upper and lower contacts, the capacitor discharges into the resistorr parallel with it, but when it reaches the lower contact, there is a voltage source charging the capacitor again - so i(t) would be a sum of the currents frm these sources?
20. ### Capacitor discharge problem

hi all, wonderign whether you can help with this problem with capacitor discharging. take a look at the pic the question is In the circuit shown above, the switch has been in the upper position for a long time and moves to the lower position at t = 0. Find i(t). Basically, first i...

bump1?! I just got the idea of staying here for my bachelors degree, then going to US to do a postgraduate degree. My reasoning is the fact taht the quality of undergraduate teaching would not vary greatly between universities (in developed countries, anyway). Plus, I get the feeling that...