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Genrish500 [490]

3 years ago

14

When a voltage difference is applied to a piece of metal wire, a 10.0 mA current flows through it. If this metal wire is now rep

laced with a silver wire having twice the diameter of the original wire, how much current will flow through the silver wire?

1 answer:

Mrrafil [7]3 years ago

6 0

Answer:

10 mA

Explanation:

We have given when a potential difference is applied then a current of 10 mA is flows so current i = 10 mA

According to ohms law voltage V =i R

And resistance is given as $R= \frac{\rho l}{A}$

From the relation it is clear that resistance is inversely proportional to the area

As in new case the wire have twice diameter means 4 times the area so the resistance will decrease by 4 times from the previous resistance

As current $i=\frac{V}{R}$ current is inversely proportional to resistance so current will become 4 times of previous value

So current = 10×4=40 mA

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