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: Calculating Operating temperatures

  1. Sep 15, 2009 #1
    1. The problem statement, all variables and given/known data
    I have to calculate the working temperature of a tungsten element, i have the following info:
    (at room temp) Resistance: 4.6 ohms
    current: 0.150A
    Voltage: 6V
    Wire Length: 25mm
    Wire Diameter: 0.025mm
    Temp Coefficient: 0.0044

    3. The attempt at a solution
    I've tried using Joules first law (http://en.wikipedia.org/wiki/Joule_heating Q ~= I^2 * R) but get ridiculous answers like 0.09K and 103k.

    * "~=" means proportional to

    If anyone can give me a simple equation to work this out as well as an example I'd be VERY grateful, thanks in advance.
  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