Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Need help with a calculus problem?

  1. Feb 22, 2007 #1
    Try http://www.mathcasts.org/db_calc/main_view.php .

    I just did a google search for a specific type of problem I was struggling with and this website helped a lot. I can't guarantee that all the videos are accurate, but there are lots of them(note that there are 6 pages) and they seem fine to me.

    Enjoy. :smile:

    Find the topic you are interested in and click "mathcast".

    Even though they are geared towards a specific textbook, its all the same stuff so if you are stuck on an topic, you may be able to find info about it here.
    Last edited: Feb 22, 2007
  2. jcsd
  3. Feb 25, 2007 #2
    Some of the links are dead.
  4. Feb 28, 2007 #3


    User Avatar

    Thanks and links fixed

    Thanks dontdisturbmycircles for the kind words about the mathcasts and thanks minase for noticing the dead links - which hopefully are now fixed! LFS
  5. Mar 5, 2007 #4
    Dear god, she did a problem with a constant voltage ('electric pressure')

    What the............'electric pressure'..............sigh......
  6. Apr 11, 2007 #5
    Systems Dynamics


    In Systems Dynamics 101, any system can be described using equations whereby an EFFORT variable induces a FLOW variable. These equations are usually only to 2nd order (2nd derivative.)

    Some examples: Electrical voltage induces a current; current is affected by resistance. Pressure difference induces fluid flow -- which is affected by pipe friction. Temperature difference induces heat transfer -- which is affected by insulation. Difference of forces induces motion -- which is affected by rolling (or sliding) friction. Similarly for rotational momentum systems, diffusion systems, or any other system.

    Make a chart of these various systems, their effort and flow variables and the governing equations for each. You will understand what she meant by "electrical pressure." BTW, it is common to use fluid flow analogies to describe electrical systems, and vice versa.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook