1. Homework Help

   1. Introductory Physics Homework

      Meaning of a phrase in a kinematics problem.

   2. Advanced Physics Homework

      Multi particle QM

   3. Precalculus Mathematics Homework

      Why does the cross product of two direction vectors...

   4. Calculus and Beyond Homework

      Instantaneous rate of change and deriving a fraction

   5. Biology, Chemistry and Earth Homework

      Which mechanism and which step would best fit the data?

   6. Engineering and Computer Science Homework

      What is the gain error for this opamp driven by a voltage

2. Science Education and Careers

   1. Science and Math Textbooks

      Multivariable calculus without forms or manifolds

   2. Academic Guidance

      Trouble getting past Algebra 2

   3. Educators and Teaching

      Hall's Marriage Theorem

   4. Career Guidance

      How much money can you make in physics?

3. Physics

   1. General Physics

      Augmentation Energy Cell

   2. Classical Physics

      Contradicting values of pressure for liquid cross-sections

   3. Quantum Physics

      What happens to entanglement inside a polarizer?

   4. Special and General Relativity

      Time Dilation Theory Flaw

   5. Atomic and Condensed Matter

      High pressure superconductors

   6. High Energy, Nuclear, Particle Physics

      Fields transforming in the adjoint representation?

   7. Beyond the Standard Model

      ER=EPR baby steps: causation or not?

4. Astronomy and Cosmology

   1. Astronomy and Astrophysics

      Can we see our past?

   2. Cosmology

      Total number density of galaxies and problematic expression

5. Mathematics

   1. General Math

      Why can't I reach every cell in a 3x3 square?

   2. Calculus

      A Numerical Insight for the Fundamental Theorem of Calculus - Comments

   3. Differential Equations

      Chaos Theory Constants

   4. Topology and Analysis

      Trying to understand why a set is both open and closed

   5. Linear and Abstract Algebra

      How to properly understand finite group theory

   6. Differential Geometry

      Tangent spaces at different points

   7. Set Theory, Logic, Probability, Statistics

      Probability that a Random String is a Word

   8. MATLAB, Maple, Mathematica, LaTeX, Etc

      Problem with line integrals in Mathematica

6. Engineering

   1. General Engineering

      Using the thermosyphon effect for a floor water heating system

   2. Mechanical Engineering

      Normal load on the tires of car

   3. Electrical Engineering

      dB scale misunderstanding

   4. Materials and Chemical Engineering

      Searching for a strong inflexible plastic that is transparent

   5. Nuclear Engineering

      Current State of Nuclear Fusion Power

   6. DIY Projects

      Recommendations: Project inspiration w/ a budget

7. Other Sciences

   1. Chemistry

      CO2 [ppm] exposure relative to room volume [m^3] and air ventilation

   2. Programming and Computer Science

      A good chatbot database that can scale

   3. Biology and Medical

      Why does photosynthesis produce O2 from CO2?

   4. Computing and Technology

      Can't see PDF contents as well as Google does

   5. Earth

      Freezing fog creates rare light pillars in Wisconsin on Sunday

8. Uncategorized Thought Field

   1. 2018 PF Member Award Polls

      Thank You PF Mentors!

   2. General Discussion

      American & Canadian PF members only: colonial roots?

   3. Science Fiction and Fantasy Media

      Sci-fi author needs advice on building a multi-layered city

   4. Feedback and Announcements

      2018 PF Member Awards Are Coming!

   5. New Member Introductions

      Introduction Only

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