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: Zero adjust resistance help please?

  1. Jan 13, 2015 #1
    • Member warned about using template for posts in the Homework Sections of PF.
    hello there i kinda need help with this, image attached in the thread
    this is the ohmmmeter circuit and i have two questions :
    -what is the effect of R2 when it become lower than Rm?
    -what is the effect of R2 when it become higher than Rm?

    Rm=internal resistance of ohm-meter
    R2=zero adjust resistance

    edit:i study computer engineering techniques and this is the instrument and measurements
    so hopefully this is the right place to post

    Attached Files:

    Last edited: Jan 13, 2015
  2. jcsd
  3. Jan 13, 2015 #2


    User Avatar

    Staff: Mentor

    In your figure the bottom end of R2 is connected to the node where E and Rm connect, but the "wire" looks more sketchy than the other wires of the drawing. Is that connection intentional?

    You need to make an attempt at a solution before we can offer any detailed help. Here's a hint though: You've identified R2 as a zero adjust resistance. What's the standard procedure for zero-adjusting an ohmmeter? Think about comparing the magnitudes of the currents passing through the meter Rm and R2.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted