Why does the current increase when the potential differene stays constant?

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The discussion centers on the phenomenon of increasing current through a specimen with a constant potential difference. Initially, it was suggested that rising temperature decreases resistance, leading to increased current; however, this was corrected to indicate that higher temperatures actually increase resistance in metal wires. The lack of clarity about the specimen's characteristics, such as its dimensions and material properties, complicates the analysis. Despite the constant voltage, the current's increase may be attributed to other factors not fully explored in the conversation. The relationship between temperature, resistance, and current remains a key point of confusion.
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A specimen has a potential difference applied, which remains constant throughout. The current through the specimen increases substantially though. Why does it increase?

Is this to do with the temperature of the wire increasing and so resistance decreases and the current therefore increases. But the potential difference won't be affected as it is constant in voltage.

Is this right at all? Or totally wrong?

Many Thanks!
 
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You're saying the temperature dependency backwards. If the temp of a metal wire increases then the resistance would increase.

To say that you're testing a specimen isn't really enough information. It doesn't sound clear whether the object under test might contain any switches or fuses or diodes, etc., or is able to be stretched into a new shape, or it's chemical composition is being altered, etc. Is it known to be simply a metal wire of constant dimensions? Are you expected to determine whether or not it is a metal wire?
 
Last edited:
mikelepore said:
To say that you're testing a specimen isn't really enough information. It doesn't sound clear whether the object under test might contain any switches or fuses or diodes, etc., or is able to be stretched into a new shape, or it's chemical composition is being altered, etc. Is it known to be simply a metal wire of constant dimensions? Are you expected to determine whether or not it is a metal wire?

Sorry, no it doesn't contain any switches etc. but is just a piece of metal wire.

So as the temperature in the wire increases, the resistance also increases. But how does this make the current increase if the voltage is constant?

Thanks.
 
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