The resistance of a wire of length L and radius r in R. Which one of the following would provide a wire of the name material of resistance $\frac{R}{2}$ ?

Question

YESPYQ · Accepted Answer

Correct answer: b) Using a wire of same radius and half length. B. Using a wire of same radius and half length New Length $L' = \frac{L}{2}$, New Radius $r' = r$. $$R' = \rho \frac{L/2}{\pi r^2} = \frac{1}{2} \left( \rho \frac{L}{\pi r^2} \right) = \frac{R}{2}$$ (This is correct).

The resistance of a wire of length L and radius r in R. Which one of the following would provide a wire of the name mate…

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