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: Dimensinoal analysis?

  1. Feb 2, 2008 #1
    IM not even sure how to go about solving this problem, but its due Monday morning

    rectangular plate has a length of 23.2 +/- .2 cm and a width of 9.0 +/- .1 cm. calculate the area and its uncertainty......
  2. jcsd
  3. Feb 2, 2008 #2
    Well, what would you do to start? Suppose someone just came up to you and said, "I've got a rectangular plate here in my bag, and it's around 23.2 cm by about 9 cm." What would you estimate the area to be?

    Once you have that, how far could you be off from the real answer, given the uncertainties stated in the problem? In other words, what the largest area that could be correct, given those uncertainties, and what's the smallest area that could be correct? The difference shows you the uncertainty in the answer.

    If you can answer those questions, then you can probably see how to get the uncertainty in the answer from the given uncertainties in the provided information.
  4. Feb 2, 2008 #3
    Let's start with the length of the plate. When you say the length is 23.2 +/- 0.2 cm, what does that mean physically?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook