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3 years ago

15

A gold wire has a cross-sectional area of 1.0 cm^2 and a resistivity of 2.8 × 10^-8 Ω ∙ m at 20°C. How long would it have to be

to have a resistance of 0.001 Ω?

1 answer:

Karo-lina-s [1.5K]3 years ago

4 0

Answer:

Length, l = 3.57 meters

Explanation:

It is given that,

Area of cross-section of gold wire, $A=1\ cm^2=0.0001\ m^2$

Resistivity of gold wire, $\rho=2.8\times 10^{-8}\ \Omega-m$

Resistance, R = 0.001 ohms

Resistance in terms of length and area is given by :

$R=\rho \dfrac{l}{A}$

$l=\dfrac{RA}{\rho}$

$l=\dfrac{0.001\times 0.0001}{2.8\times 10^{-8}}$

l = 3.57 meters

So, the length of the wire is 3.57 meters. Hence, this is the required solution.

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Answer:

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Hello! In this problem we have a uniformly varied rectilinear movement.

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α =69.2

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Part a)

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$x = 0$

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$v = \frac{\pi}{2\sqrt2}$

at t = 2

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Average acceleration is given as

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now we have

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