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Homework Help: OCR Physics AS Level - Strain gauge, temperature, resistance

  1. May 11, 2008 #1
    I have an assignment in which I have to design a laboratory experiment (not real, only in theory i.e. planning) to investigate how the resistance of a strain gauge attached to a piece of wood varies with the temperature of the wood.

    *IMPORTANT* My teacher said keep it simple, do not over complicate things. Only school lab equipment is allowed. I have to also make predictions, make a graph (temp vs resistance??), and a sample table (prelimanary results).

    So far I have come up with stupid ideas like getting a piece of wood, making a hole, sticking a thermometer in it and then place the whole thing in a beaker. Heating up the beaker with bunsen burner (beaker will be on a tripod) and then taking readings off the thermometer. Obviously there is one big problem, where does the strain gauge come in? Do I have to attach it to the wood, if so, then how do I take the readings of the resistance.

    I have other ideas such as attaching the strain gauge using glue onto the piece of wood and then some how connecting this in a circuit, but what components would I use, how would I measure the resistance, how to connect it up and heat up the wood and record temperature??

    The official question of this planning exercise is: You are required to design a laboratory experiment to investigate how the resistance of a strain gauge attached to a piece of wood varies with the temperature of the wood.

    I have just registered on this forum, although I have been a lurker for quite some time now. If all goes well then I'll probably become an active member here.

    Basically, I need a step-by-step method/procedure on this if possible. I also gotta include a diagram and a possible circuit diagram too? Also have to list the apparatus I'm going to use.


    ~FF
     
  2. jcsd
  3. May 12, 2008 #2
    Bump. :smile:


    EDIT: Does the formula R=pL/A have anything to do with this? Or R=V/I?

    Also, I was thinking water baths at different constant temperatures but come to think of it I guess that's not gonna work lol.

    EDIT: What do you think of this >> Using a power pack, connect ampmeter and strain-gauge-glued-on-wood-with-a-thermometer-in-it, making a circuit. Then heating up the wood with Bunsen burner and recording the temps and resistance.

    ~FF
     
    Last edited: May 12, 2008
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