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    I'm only stuck on one part at the end but I will write out the full question:

    A potential divider consists of an 8.0 resistor in series with a 4.0 resistor and a 6.0V battery of negligible internal resistance. Calculate
    i) the current (done)
    ii) the pd across each resistor (done)

    b)
    In the circuit above the 4 resistor is replaced by a thermistor with a resistance of 8 at 20C and a resistance of 4 at 100C. Calculate the pd across the fixed resistor at
    i) 20 C (done) (answer 3V)
    ii) 100C

    I did for B ii) 6.0x4.0 / 12 and I get the answer of 2V yet the textbook says the answer is 4V but i've got the questions right so far, is this a textbook error or am I not seeing something.

    Thanks
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    (Original post by Cinna21)
    I'm only stuck on one part at the end but I will write out the full question:

    A potential divider consists of an 8.0 resistor in series with a 4.0 resistor and a 6.0V battery of negligible internal resistance. Calculate
    i) the current (done)
    ii) the pd across each resistor (done)

    b)
    In the circuit above the 4 resistor is replaced by a thermistor with a resistance of 8 at 20C and a resistance of 4 at 100C. Calculate the pd across the fixed resistor at
    i) 20 C (done) (answer 3V)
    ii) 100C

    I did for B ii) 6.0x4.0 / 12 and I get the answer of 2V yet the textbook says the answer is 4V but i've got the questions right so far, is this a textbook error or am I not seeing something.

    Thanks
    you might be calculating the PD across the other resistor by accident
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    (Original post by Joinedup)
    you might be calculating the PD across the other resistor by accident
    Are you sure ? did you work out the question and get 4 ? please help I'm confused
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    (Original post by Cinna21)
    Are you sure ? did you work out the question and get 4 ? please help I'm confused
    at 100 deg C you've got an 8 ohm fixed resistor in series with a 4 ohm thermistor

    across both resistors in series you've got the supply voltage (6V)

    across the 8 ohm you've got supply voltage x 8/(8+4)
    across the 4 ohm you've got supply voltage x 4/(8+4)

    you're being asked about the fixed (8 ohm) resistor
 
 
 
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