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2 years ago

In which situation will the lowest resistance occur?

Physics

1 answer:

MrMuchimi2 years ago

7 0

C. Thick wire and cold temperature.

Explanation:

The resistance of a wire is given by: R = (ρL)/A

where ρ is the resistivity of the material, L is the length of the wire, A is the cross-sectional area of the wire.

From the formula, we see that the thicker the wire, the larger A, therefore the smaller the resistivity. so, a thick wire will have lower resistivity.

Moreover, the resistance of a wire increases with the temperature. In fact, high temperatures mean more motion of the atoms/electrons inside the wire, so more resistance to the flow of current through it. Therefore, colder temperature means lower resistance.

So, the correct option is thick wire and cold temperature.

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