# Recent content by maxhersch

1. ### Other Not enough time

I am in my 4th year (3 semesters left including the current one), taking mechanics, E&M, quantum mechanics, and a lab course. For each of the three main courses, we get one problem set per week that's around 5-8 questions. In addition to that there's a lab report due every 1-2 weeks. It really...
2. ### B I want to define a function knowing only it's limits

This is a random problem I am trying to figure out. The context doesn't matter. I wish to define a function z(x, y) based on the following limits: 1. lim z (x→∞) = 0 2. lim z (x→0) = y 3. lim z (y→∞) = ∞ 4. lim z (y→0) = 0
3. ### I Entries in a direction cosine matrix as derivatives

This is a somewhat vague question that stems from the entries in a directional cosine matrix and I believe the answer will either be much simpler or much more complicated than I expect. So consider the transformation of an arbitrary vector, v, in ℝ2 from one frame f = {x1 , x2} to a primed...
4. ### I Kronecker Delta and Gradient Operator

I am looking at an explanation of the gradient operator acting on a scalar function $\phi$. This is what is written: In the steps 1.112 and 1.113 it is written that $\frac {\partial x'_k} {\partial x'_i}$ is equivalent to the Kronecker delta. It makes sense to me that if i=k, then...
5. ### Double Integration in Polar Coordinates

Yep, just remembered that right as your replied. Thanks
6. ### Double Integration in Polar Coordinates

1. Homework Statement Integrate by changing to polar coordinates: $\int_{0}^6 \int_{0}^\sqrt{36-x^2} tan^{-1} \left( \frac y x \right) \, dy \, dx$ 2. Homework Equations $x = r \cos \left( \theta \right)$ $y = r \sin \left( \theta \right)$ 3. The Attempt at a Solution So this...
7. ### Estimate Vector Field Surface Integral

Perfect thanks a lot
8. ### Estimate Vector Field Surface Integral

I assume this is a simple summation of the normal components of the vector fields at the given points multiplied by dA which in this case would be 1/4. This is not being accepted as the correct answer. Not sure where I am going wrong. My textbook doesn't discuss estimating surface integrals...
9. ### Gravitational Lensing and Angular Diameter Distances

1. Homework Statement Given this diagram, the problem is to find an expression for β/ΘE in terms of X/ΘE and Y/ΘE. 2. Homework Equations β = Θ – α(Θ) Dsβ = DsΘ – Dlsα'(Θ) 3. The Attempt at a Solution I really only need help starting this problem. In my textbook and every document I can...
10. ### Testing Difficulty with Modern Physics Midterm

2-3 hours is just on the one homework assignment that is due each week. That does not count time spent studying for the weekly quizzes or just reviewing lecture material. And also the same question in my reply above is really what I was looking for. Thanks.
11. ### Testing Difficulty with Modern Physics Midterm

Sorry I didn't mean to sound like I'm not interested in learning the harder problems but I am in multivariable calculus, advanced statistics, and principles of astrophysics as well and I don't just have time to be delving into subjects I don't think I will be tested on. Believe me I would love...
12. ### Testing Difficulty with Modern Physics Midterm

I am currently in Honors Physics 3 which is the third introductory course of my physics degree program and covers modern physics beginning with special relativity. So far we have covered Lorentz transformations and velocity additions, relativistic energy and momentum, blackbody radiation, photon...
13. ### I Find the formula to express the infinite series...

Never mind I figured it out $$a_n = \frac {9 - 7 \{ -1 \} ^n} {2 \{ 1 + n^2 \}}$$
14. ### I Find the formula to express the infinite series...

The problem is to find the general term $a_n$ (not the partial sum) of the infinite series with a starting point n=1 $$a_n = \frac {8} {1^2 + 1} + \frac {1} {2^2 + 1} + \frac {8} {3^2 + 1} + \frac {1} {4^2 + 1} + \text {...}$$ The denominator is easy, just $n^2 + 1$ but I can't think of...
15. ### SigFigs in Volume and Uncertainty?

Thanks, so just to be clear that would mean that I should express the change in volume and the uncertainty in the change in volume to the nearest thousandth of a centimeter because they were measured to that degree of accuracy in the question, right?