1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Determining Constants in Equataions

  1. Oct 13, 2007 #1
    1. The problem statement, all variables and given/known data

    In all the following problems state the variables or combination of variables
    which should be plotted to check the suggested variation and state how the unknown
    may be found ( through the slope and/or intercept of the best fitting straight line
    y = m x + b.). Because you are not given any numerical data it is just required to
    qualitatively describe you method of solution in few lines with schematic graphs.

    here are a couple of examples:
    The gas law for an ideal gas is PV = RT , P and T are measured variables, V is fixed and
    known. Determine R.

    The linear expansion of a solid is described by ℓ = ℓo ( 1 + α.Δt ) where ℓ and Δt are
    measured variables, ℓo is constant but unknown. Determine α .

    3. The attempt at a solution

    For the first one:
    An increase in T will yield an increase in P because V is a fixed value. P is therefore the dependent variable while T is the independent variable. R is the coefficient to T therefore it will be the slope when P vs T is graphed.

    My question is mainly how would I go about problems like this or more complicated than this. When it gives you an equation, two measured values, and a third one which is supposed to be a constant like g. How would you determine the constant?
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted