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: Wheatstone Bridge Problem

  1. Apr 13, 2008 #1
    My teacher gave us this problem to work on:

    1. The problem statement, all variables and given/known data
    Some years ago I worked with a geophysical group that was looking for water in the Yuma Arizona area. Boy what it hot! Because of the high temperatures in the summer, water was badly needed in large amounts to irrigate crops. Our crew inserted probes in the soil over large areas so we could measure the resistance of the soil and hopefully find water. The instrument that we used in this research was a Leeds and Northrup unit just like the one you used in your experiment. We did not use a slide-wire bridge. Give three reasons why a professional crew like I have described used a L&N bridge rather than the slide-wire bridge.

    2. The attempt at a solution

    1. A L&D bridge is far more accurate than a slide-wire bridge is in this situation.
    2. It is more portable.
    3. The heat may cause the wire in the slide-wire bridge to shrink/expand and cause discrepancies in the data.

    The last two are just shots in the dark because I can't think of anything else beyond accuracy.
  2. jcsd
  3. Apr 13, 2008 #2
    No one?
  4. Apr 13, 2008 #3
    Please? lol
  5. Apr 13, 2008 #4
    I think 1) is because of 3) which is the correct answer. I am not very sure what an L&D bridge is though. I assumed they consisted of the arrangement of resistor boxes usually seen in labs.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook