Recent content by StillAnotherDave

Thanks. I approached it along these lines but failed to make the flow rate conversion!

By conservation of energy here you mean W=p1v1 - p2v2? The question doesn't give the pressure inside the box. Are we assuming its the same as outside or does it need to be worked out? I'm wondering the dE=CvdT needs to be factored in, for a diatomic gas. Would v1 be 5 litres? If so, what is v2?

Hello folks, I have a bit of a time sensitive question, if anyone happens to read this soon. A computer box consumes 80W power constantly. Outside temperature T= 290 Kelvin. Ambient pressure 10^5. If all the heat generated is expelled at 5 litres per second, estimate the inside...

This makes perfect sense! Thoroughly appreciate the careful explanation.

Thanks for the really useful help! Can I just ask about the second part of Q1 where the iris acts as a stop limiting the angle. Is there any simple example question/notes you can point me to for this? I get the basic idea but am not exactly sure of how to proceed.

I've been trying to read around. I can't find a clear connection between spatial resolution and pixel size (Q2), but it seems that there's a dependency on the height of the satellite.. is that correct? And for Q1 is this something to do with angular resolution once you introduce the eye?

Hello folks, I have the two following questions I'm working on: Q1 An optical microscope uses a lens with NA = 0.7 and a focal length of f = 20 mm. What is the smallest spatial distance that can be resolved if a wavelength of λ = 633nm is used? An iris is introduced in front of the lens with a...

Interesting. Let me pose the question slightly differently to see if it helps answer what I'm looking for. If we imagine an infinitely long thin wire aligned along the z-axis. What (simple) methods could we use to determine if B is conservative outside the wire? My understanding was that if the...

Quick question, if a vector field contains a singularity, how does one show whether it is conservative or not? Can you still verify this by finding a scalar potential such that the gradient of the scalar potential is equivalent to the vector field?

That's very helpful!

So my basic understanding is that you can relate the polar angle to the Cartesian system through the following: ##x=rcos\theta## ##y=rsin\theta## Is that the relevant connection? P.s. thanks for highlighting the inconsistency with phi and theta.

That's a good question. I already anticipated that if I am missing something in my working it's likely to be with working out how to integrate the ##\theta## component. But if the line integral runs in the i and j directions (thereby integrating from -a to a in each of the four paths), how does...

Hello folks, I'm working on a question as follows: I appreciate that there might be more sophisticated ways to do things, but I just want to check that my approach to the line integral is accurate. I will just give my working for the first side of the path. So I have set up the path as a...

Hello all, I have produced a contour plot of a given function f. To this, I have added the vector field (arrows) for the gradient of f calculated analytically. I have then also added the vector field numerically by using the np.gradient function in python. In both cases, the vector field...

Thank you gentlemen. This was along the lines of my original solution but seemed far too simple an answer. Perhaps Covid has simply made question setters more compassionate.