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Physics past papers question

IF temperature of circuit increases , what will be the result for current and potential difference?
current increase and potential dfference decreases.
i don't understand why the pd decreases?
Isn't it cus with more temperature there is more resistance? V=IR and all that
Original post by Rosie1999
IF temperature of circuit increases , what will be the result for current and potential difference?
current increase and potential dfference decreases.
i don't understand why the pd decreases?


The current should decrease due to more vibrating latttice ions which offer more resistance to current flow NO?
(edited 7 years ago)
Original post by AlvlVictim
The current should decrease due to more vibrating latttice ions which offer more resistance to current flow NO?


And as I and V are directly proportional to each other so p.d decreases as well
Reply 4
Original post by Rosie1999
IF temperature of circuit increases , what will be the result for current and potential difference?
current increase and potential dfference decreases.
i don't understand why the pd decreases?


I'm pretty certain thats wrong unless their is an ntc resistor in your circuit?
Original post by Rosie1999
IF temperature of circuit increases , what will be the result for current and potential difference?
current increase and potential dfference decreases.
i don't understand why the pd decreases?


If the temperature of a circuit increases for a component, there will be more collisions between lattice ions and charge carriers (electrons) thus resulting in a higher resistance.
Not sure where this question is from but it seems incorrect. Potential difference must increase in order for the current to increase for a higher resistance.
But for more current to a flow a higher PD is needed so as R increases, so does I and so does V. We use V=IR to determine what increases and decreases.

Unless the question is about a thermistor. In which case as temperature increases, resistance decreases which means you need less PD for a fixed current. << This would make sense for your question
(edited 7 years ago)

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