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Current Electricity question - Marking scheme and examiner report included

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Can someone please explain 2. of c) As you can see, the marking scheme says that the voltmeter reading will increase due to greater current flow and something something about potential dividers. But the concept eludes me. Can someone please explain WHY the voltmeter reading increases ?
 
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The 6 volts from the battery are to be shared between the fixed resistor and the thermistor. The amount of voltage that each resistor receives is proportional to its resistance. The voltmeter measures the resistance across the fixed resistor only. When the temp. increases the resistance of the thermistor decreases. This means that the thermistor now receives less voltage (since voltage is proportional to resistance) and more voltage goes to the fixed resistor.
 
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Look, as you know, thermistor resistance will decrease, so the resistance of other resistor will increase that is connected across voltmeter, so as R prop to V R increases, V increases.
 
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