Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    13
    ReputationRep:
    I've plotted a graph of resistance vs temperature and this is it: <br />
    <br />
    I have then enlarged a portion of the graph to find a certain temperature change at a two specific resistances: <br />
    <br />
    The faded vertical lines indicate the change in temperature. <br />
    <br />
    My question is, I've used a thermometer (+/- 1 degree uncertainty) but the temperature change is 0.32*C so how would I find the uncertainty in that? (My scalar uncertainty is greater than the value itself)
    Offline

    11
    ReputationRep:
    (Original post by munchen102)
    I've plotted a graph of resistance vs temperature and this is it: <br />
    <br />
    I have then enlarged a portion of the graph to find a certain temperature change at a two specific resistances: <br />
    <br />
    The faded vertical lines indicate the change in temperature. <br />
    <br />
    My question is, I've used a thermometer (+/- 1 degree uncertainty) but the temperature change is 0.32*C so how would I find the uncertainty in that? (My scalar uncertainty is greater than the value itself)
    How did you measure a change of less than a degree with a thermometer that is only accurate to one degree?
    The uncertainty applies to the reading, not to the delta.
    • Thread Starter
    Offline

    13
    ReputationRep:
    (Original post by joostan)
    How did you measure a change of less than a degree with a thermometer that is only accurate to one degree?
    The uncertainty applies to the reading, not to the delta.
    I didn't. I took several readings at 0,5,10,20,30 up to 90*C and then plotted a graph of resistance vs temp. I then used this graph (graph1) to measure the small temperature change at a certain change in resistance.

    So the ΔT wouldn't have an uncertainty?
    Offline

    11
    ReputationRep:
    (Original post by munchen102)
    I didn't. I took several readings at 0,5,10,20,30 up to 90*C and then plotted a graph of resistance vs temp. I then used this graph (graph1) to measure the small temperature change at a certain change in resistance.

    So the ΔT wouldn't have an uncertainty?
    The uncertainty applies to the measured values, e.g. 0, 5, 10, 20 etc. It does not apply to ΔT, in so many words, it applies to the points at either end, but not the ΔT itself.
    • Thread Starter
    Offline

    13
    ReputationRep:
    (Original post by joostan)
    The uncertainty applies to the measured values, e.g. 0, 5, 10, 20 etc. It does not apply to ΔT, in so many words, it applies to the points at either end, but not the ΔT itself.
    Thanks I understand that. So is there any uncertainty in the value taken from the graph?
    Offline

    11
    ReputationRep:
    (Original post by munchen102)
    Thanks I understand that. So is there any uncertainty in the value taken from the graph?
    In the ΔT? Yes but it's complicated to work out and probably not required for whatever it is you're doing.
    • Thread Starter
    Offline

    13
    ReputationRep:
    (Original post by joostan)
    In the ΔT? Yes but it's complicated to work out and probably not required for whatever it is you're doing.
    Thank you much appreciated.
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Has a teacher ever helped you cheat?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Write a reply...
    Reply
    Hide
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.