1. Homework Help

   1. Introductory Physics Homework

      Rotating rod with two masses

   2. Advanced Physics Homework

      how to find eigenvalues and eigenfunction

   3. Precalculus Mathematics Homework

      Error bar calculation (statistics)

   4. Calculus and Beyond Homework

      Integral of 1/(a sin^2 x + b sin x cos x + c cos^2 x)

   5. Biology, Chemistry and Earth Homework

      Genetics Problem 1

   6. Engineering and Computer Science Homework

      Sketch the waveform to represent the transient response

2. Science Education and Careers

   1. Science and Math Textbooks

      A free modern introduction to astronomy textbook

   2. Academic Guidance

      How much time should I study?

   3. Educators and Teaching

      Helping students transition from High School to University

   4. Career Guidance

      Jumping to engineering

3. Physics

   1. General Physics

      Fermat's Principle

   2. Classical Physics

      Does an ideal fluid have zero surface tension?

   3. Quantum Physics

      Why all particles of same type identical?

   4. Special and General Relativity

      Help with constant acceleration under special relativity

   5. Atomic and Condensed Matter

      Two questions on Feynman diagram and Green's function

   6. High Energy, Nuclear, Particle Physics

      Gamma Decay (Electric and Magnetic Transitions)

   7. Beyond the Standard Model

      Is string theory a deterministic hidden variable theory?

4. Astronomy and Cosmology

   1. Astronomy and Astrophysics

      Synchronous orbits.

   2. Cosmology

      WIMP , dark matter

5. Mathematics

   1. General Math

      verifying an equality

   2. Calculus

      Evaluating an integral issue

   3. Differential Equations

      Derivation of Lax-Wendroff finite volume scheme

   4. Topology and Analysis

      Understanding the "branch cut argument"

   5. Linear and Abstract Algebra

      How to keep the components of a metric tensor constant?

   6. Differential Geometry

      Do Isometries Preserve Covariant Derivatives?

   7. Set Theory, Logic, Probability, Statistics

      Probability Theory: Multinomial coefficients

   8. MATLAB, Maple, Mathematica, LaTeX, Etc

      from CSV to single page PDF

6. Engineering

   1. General Engineering

      Bridge Collapse Genoa - Informed Engineering Perspectives

   2. Mechanical Engineering

      Propeller - Rearward flow of air

   3. Electrical Engineering

      Mosfet replacement

   4. Materials and Chemical Engineering

      Is there a way to increase the efficiency of spdc?

   5. Nuclear Engineering

      Resource(s) for commercial transuranic waste composition?

   6. DIY Projects

      Tips to keep your house cool in summer

7. Other Sciences

   1. Chemistry

      In co-ordinate bond, why H^+ atom don't get negative charge?

   2. Programming and Computer Science

      Inputting Data into SAS

   3. Biology and Medical

      Caesalpinia seeds

   4. Computing and Technology

      Can a 2-D barcode scanner be used with OCR applications?

   5. Earth

      Mag. 7 Indonesia Earthquake - 5th August 2018

8. PF Lounge

   1. General Discussion

      Anybody interested in the Philosophy / Sociology of Science?

   2. Science Fiction and Fantasy Media

      Contact, The Movie

   3. Feedback and Announcements

      PF Server Move

   4. New Member Introductions

      Hi everyone

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