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    It is suggested that the relationship between 1/I and x is:
    1/I = (ρ/AV)x + k

    where ρ is the resistivity of the wire, A is the cross-sectional area of the wire, V is the potential difference of the power supply and k is a constant for the circuit..
    Using the value for the gradient and your other results determine a value for the resistivity ρ with an appropriate unit.
    
    Does anyone know how to answer these type of questions? I have my coursework tomorrow. All I know is that it has something to do with y = mx +c
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    (Original post by Elhamm)
    It is suggested that the relationship between 1/I and x is:
    1/I = (ρ/AV)x + k

    where ρ is the resistivity of the wire, A is the cross-sectional area of the wire, V is the potential difference of the power supply and k is a constant for the circuit..
    Using the value for the gradient and your other results determine a value for the resistivity ρ with an appropriate unit.
    
    Does anyone know how to answer these type of questions? I have my coursework tomorrow. All I know is that it has something to do with y = mx +c
    In general, this type of question requires you to linearise the suggested relationship.

    Ex. E_k=\dfrac{1}{2}mv^2
    you need this to be a straight line so you can find out the mass by measuring the gradient. So you plot kinetic energy on the y-axis and v^2 on the x-axis.

    For your equation you need to pick something for y to equal and something for x to equal. Then the gradient will be resistivity (or some multiple of it).
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    (Original post by lerjj)
    In general, this type of question requires you to linearise the suggested relationship.

    Ex. E_k=\dfrac{1}{2}mv^2
    you need this to be a straight line so you can find out the mass by measuring the gradient. So you plot kinetic energy on the y-axis and v^2 on the x-axis.

    For your equation you need to pick something for y to equal and something for x to equal. Then the gradient will be resistivity (or some multiple of it).
    How would I work out the units required using my equation?
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    (Original post by Elhamm)
    How would I work out the units required using my equation?
    Units for what? To work out units you can use the rules

    • both sides must have the same units
    • any time you add two quantities, they must have the same units (you can't add metres to kilograms)
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    (Original post by lerjj)
    Units for what? To work out units you can use the rules

    • both sides must have the same units
    • any time you add two quantities, they must have the same units (you can't add metres to kilograms)
    For finding resistivity.
    I tried solving this equation but I was still unable.
    can you please show me how to work it out step by step using any example figures for y-axis, x-axis and gradient??
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    (Original post by Elhamm)
    It is suggested that the relationship between 1/I and x is:
    1/I = (ρ/AV)x + k

    where ρ is the resistivity of the wire, A is the cross-sectional area of the wire, V is the potential difference of the power supply and k is a constant for the circuit..
    Using the value for the gradient and your other results determine a value for the resistivity ρ with an appropriate unit.
    
    Does anyone know how to answer these type of questions? I have my coursework tomorrow. All I know is that it has something to do with y = mx +c
    What do I and x stand for?

    Assuming that you have measured: I, A, V, and x for some experiment the way to check if your relationship is true is to construct a graph which should be a straight line.

    Straight lines are in the form y=mx+c
    your's is in the form (1/I)=(some numbers)x+k

    do you see the similarity?
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    (Original post by lerjj)
    What do I and x stand for?

    Assuming that you have measured: I, A, V, and x for some experiment the way to check if your relationship is true is to construct a graph which should be a straight line.

    Straight lines are in the form y=mx+c
    your's is in the form (1/I)=(some numbers)x+k

    do you see the similarity?
    I stands for current and x stands for the lenght of the wire
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    (Original post by Elhamm)
    I stands for current and x stands for the lenght of the wire
    Ok, basically what you have to do is choose something for y to equal and something for x to equal when you plot your graph- in this case you would most likely plot 1/I on the y axis and x on the x axis.

    Look at your function and see if you can tell what the gradient and y intercept of the resulting line will be.
 
 
 
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