1. Homework Help

   1. Introductory Physics Homework

      Ideal Gas Law

   2. Advanced Physics Homework

      Propagating degree of freedom (GR)

   3. Precalculus Mathematics Homework

      Angle between a plane and a line

   4. Calculus and Beyond Homework

      Fourier Transform of 1(1+x^4)

   5. Biology, Chemistry and Earth Homework

      Which mechanism and which step would best fit the data?

   6. Engineering and Computer Science Homework

      Step Change in a proportional plus integral controller

2. Science Education and Careers

   1. Science and Math Textbooks

      Mechanical Metallurgy by George Dieter

   2. Academic Guidance

      PhD Applications with a low GPA (due to depression in my junior year)

   3. Educators and Teaching

      Order of pre-college (high school) physics textbooks

   4. Career Guidance

      Chance of getting a teaching gig with just an MS?

3. Physics

   1. General Physics

      Maximum Work Theorem : Herbert Callen

   2. Classical Physics

      Contradicting values of pressure for liquid cross-sections

   3. Quantum Physics

      Parallel Universes: Multiverse vs Many Worlds - Splits?

   4. Special and General Relativity

      Measuring Michelson–Morley light beams

   5. Atomic and Condensed Matter

      Calculation in Plasmons

   6. High Energy, Nuclear, Particle Physics

      Why is Proton Radiation this Rare in Nuclear Fission Decay?

   7. Beyond the Standard Model

      QM's interpretations vs GR

4. Astronomy and Cosmology

   1. Astronomy and Astrophysics

      From original burst, fraction of stellar mass still on the Main Sequence

   2. Cosmology

      Dark matter and energy explained by negative mass

5. Mathematics

   1. General Math

      Addition, multiplication, divison and subtraction of error

   2. Calculus

      Derivative of the area is the circumference -- generalization

   3. Differential Equations

      How to solve an ODE to find its solution

   4. Topology and Analysis

      Trying to understand why a set is both open and closed

   5. Linear and Abstract Algebra

      Proof of a simple concept , have i done this right?

   6. Differential Geometry

      Tangent spaces at different points

   7. Set Theory, Logic, Probability, Statistics

      Classification/Valuation Problem: Baseball

   8. MATLAB, Maple, Mathematica, LaTeX, Etc

      Problem with line integrals in Mathematica

6. Engineering

   1. General Engineering

      Balloon-lifted pressurized carbon fiber smokestack to carry chemicals into the upper atmosphere?

   2. Mechanical Engineering

      BLDC Motor Re-Winding

   3. Electrical Engineering

      Can a defective DRC on heat pump cause fan motor to go bad?

   4. Materials and Chemical Engineering

      Searching for a strong inflexible plastic that is transparent

   5. Nuclear Engineering

      Geiger (or other ionizing ray) Probe for Vacuum Conditions

   6. DIY Projects

      Lifting vehicles with 4 points of contact

7. Other Sciences

   1. Chemistry

      Semiconductors GaN, AlGaN -- Questions about abbreviations

   2. Programming and Computer Science

      Do I need to define __repr__() ?

   3. Biology and Medical

      Deep Carbon Observatory report

   4. Computing and Technology

      Storage of material from CD's and DVD's: cloud?

   5. Earth

      2018-12-16 Another day of storms

8. Uncategorized Thought Field

   1. 2018 PF Member Award Polls

      Physics Award

   2. General Discussion

      Lame Jokes

   3. Science Fiction and Fantasy Media

      Weapons of the future in Sci-Fi

   4. Feedback and Announcements

      RIP PF Member Morbius

   5. New Member Introductions

      Hello from an astrodynamicist in training!

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