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

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The discussion centers on the relationship between current, potential difference, and resistance in a metal wire. When a constant potential difference is applied, the current through the wire can increase due to factors such as temperature changes affecting resistance. Specifically, while it is established that the resistance of a metal wire increases with temperature, the discussion suggests that other factors may be influencing the current increase, necessitating further investigation into the specimen's properties.

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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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