Recent content by haider

Most texts will have some sort of summary at the end of the chapter but I'd say read through the theory at your own pace with an open mind and the aim of understanding physics, exams notwithstanding. I found that to be extremely fun and rewarding after (not doing so well on) my entrances in 12th.

Which exam is this? Boards or an entrance exam? You cannot go wrong with Physics (Resnick-Halliday-Krane) or University Physics (Sears-Zemansky-Young-Freedman). Try working through some of the problems, you don't have to do all of them, and see how prepared you are. You can always ask on the...

You're correct. I misremembered the condition. Differentiability implies existence of partials but the inverse is not necessarily true. This looks to be a sign that I should brush up on my multivariable calculus. :biggrin: According to Apostol (and as you said), the local existence and...

Looks correct to me. You could also evaluate the actual definition to check your answer: $$ D_{u}f(\mathbf{p}) = \lim_{h \to 0}{\frac{ f(\mathbf{p}+h\mathbf{u}) - f(\mathbf{p}) }{h} } $$ It might be nitpicking for this problem but the gradient formula is only applicable if the function is...

I'm going through Reif and had the same question. This is how I understand it: When a system ##A## with mean energy ##\bar{E}=\varepsilon## interacts (only) thermally with a system ##A^{'}## by transfering heat ##\Delta E = \varepsilon / 3##, the proportion of systems ##A## of the ensemble in...

I am not sure that is true for all (if not most) state universities, but I might be wrong. To clarify, by state university I mean universities run by state governments (Mumbai University, Pune University, etc.) as opposed to central universities (JNU. BHU, Pondicherry University, U of Hyderabad...

Got this really pretty used copy of Boas from a relative in the US (hardcover costs like 15 times the amount here in India). Plan to work through some chapters over Christmas. Also found this post-it still inside :)

Hey, Indian physics undergrad here. When you say good universities, do you mean JEE-accepting institutes? While afaik you aren't eligible to take the tests for IITs/NITs/IISERs, have you looked at state universities? I'm not sure what the age limit for those is, but I don't remember reading...

Why Lebesgue in an introductory calculus course of all places? Fwiw we did Darboux and called it Riemann too (trapezoid was part of a numerical methods course that mostly discussed better methods) but I don't think it helped me much...except in terms of gaining an appreciation for how these...

Same here but home directory instead of desk :)

Started Div, Grad, Curl And All That by H.M. Schey because I really need to (re)learn vector calculus before next semester's Griffiths based electrodynamics course. Really liking it so far.

Congratulations to all winners; you guys make it fun to lurk here :)

Can you think of the steps involved in proving something by induction and list them out? That should help you realize what you have to do.

In my stats class we used ##f_{X}(x)## for the PDF and ##F_{X}(x)## for the CDF for a given continuous random variable ##X##. I think that this is fairly standard, because most books and lecture notes I found online used it.

Just curious, which book is this problem from?