1. Not finding help here? Sign up for a free 30min 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!

How to make Resisitivity vs. Temperature graph from in-lab measurements

  1. Oct 16, 2012 #1
    We used a wheatstone bridge, which is an electric circuit consisting of four resistors.Two of the resistors are known, one resistor is a large "resistor" with dials that control the resistance, and the fourth resistor can either be a metal or semiconductor. The metal was heated to about 290 °C.

    As the metal cooled, I moved a metal slider across a metal line so that the ammeter read zero and we recorded the position of the slider every 5 degrees or so.

    A sample of the data is:

    Temperature (°C) Ratio (cm)
    190 89.7
    185 87.7
    180 87.2
    175 85.9
    170 84.6
    165 83.5
    160 81.6
    155 80
    150 77.9

    This is for a semi conductor. When I looked in a Intro to Physics book, I saw a rho (resistivity) verses temperature graph for a semiconductor. Now I wonder if I have all the data needed to make my own. If not, what can I do in this lab to obtain the necessary data?


    Also, I need to understand what "Fermi-energy" is. What are phonons? What is bandstructure, energy levels of electrons in solids, fermi distribution, densisty of states?

    I know what scattering of electrons is. The intro to physics book says that, when a metal is hot, the ions vibrate back and forth faster, and it is difficult for an electron to go through without getting pushed back.
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?