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    This is the 6 mark for the Jan 2012 paper.

    ) Describe the procedure the student would follow in order to obtain accurate and reliablemeasurements of the resistance of the wire at different temperatures between0 oC and 100 oC.

    This is what the mark scheme says :
    The candidate states that resistance is measured using an ohmmeter orvoltmeter ammeter method. The wire is heated in a beaker of water and thetemperature measured with a thermometer. Ice is added to the water andthe water is stirred as the water is heated. Details of how resistance iscalculated and how results are presented e.g. graph of resistivity againsttemperature.

    Can someone explain to me why ice is needed and why the water is stirred while heated?
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    (Original post by JustDynamite)
    This is the 6 mark for the Jan 2012 paper.

    ) Describe the procedure the student would follow in order to obtain accurate and reliablemeasurements of the resistance of the wire at different temperatures between0 oC and 100 oC.

    This is what the mark scheme says :
    The candidate states that resistance is measured using an ohmmeter orvoltmeter ammeter method. The wire is heated in a beaker of water and thetemperature measured with a thermometer. Ice is added to the water andthe water is stirred as the water is heated. Details of how resistance iscalculated and how results are presented e.g. graph of resistivity againsttemperature.

    Can someone explain to me why ice is needed and why the water is stirred while heated?
    The ice is necessary for the water to be at O oC, since there is very few ways of getting water to that temperature.
    The importance of stirring is significant, as the water must be the same temperature throughout the water bath in order for the results to be credible.

    Hope this helped
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    Ah that makes sense! Thanks so much for your help
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    (Original post by JustDynamite)
    This is the 6 mark for the Jan 2012 paper.

    ) Describe the procedure the student would follow in order to obtain accurate and reliablemeasurements of the resistance of the wire at different temperatures between0 oC and 100 oC.

    This is what the mark scheme says :
    The candidate states that resistance is measured using an ohmmeter orvoltmeter ammeter method. The wire is heated in a beaker of water and thetemperature measured with a thermometer. Ice is added to the water andthe water is stirred as the water is heated. Details of how resistance iscalculated and how results are presented e.g. graph of resistivity againsttemperature.

    Can someone explain to me why ice is needed and why the water is stirred while heated?
    The water bath only heats the water- so it can only account for temperatures above room temp (25 degrees). So the ice is needed to reduce the temperature to 0 degrees.

    You gotta stir so that the heat through the water is spread evenly- this makes the experiment accurate, like it asks in the question.

    But this question probably wont come up in tuesdays test as it came up last year
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    Yeah im not sure what's gonna come up tbh
 
 
 
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