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3 years ago

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Two cylindrical resistors are made from copper. The first one is of length L and of radius r . The 2nd resistor is of length 6L

and of radius 2r. The ratio of these two resistances R1/R2 is:

1 answer:

SVEN [57.7K]3 years ago

3 0

Answer:

$R1/R2=\frac{2}{3}$

Explanation:

From the question we are told that:

1st's Length $l=L$

1st's radius $r=r$

2nd's Length $l=6L$

2nd's radius $r=2r$

Generally the equation for Resistance R is mathematically given by

$R=\frac{\rho L}{\pi r^2}$

Therefore

$R_1=\frac{\rho L}{\pi r^2}$

And

$R_2=\frac{\rho 6L}{\pi (2r)^2}$

Therefore

$R1/R2=\frac{\frac{\rho L}{\pi r^2}}{\frac{\rho 6L}{\pi (2r)^2}}$

$R1/R2=\frac{2}{3}$

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