Question

for a wire its resistance is 2 ohm per metre is converted into circle of radius 7m find out resistance across their on their circumference making 90 degree with centre

Answer 1

Question #30219

for a wire its resistance is 2 ohm per metre is converted into circle of radius 7m find out resistance across their on their circumference making 90 degree with centre

Solution:

Let:

$$\rho = 2 \text{ ohm/m}$$ $$r = 7 \text{ m}$$ $$\alpha = 90{}^\circ$$ $$R = ?$$

$R = \rho L$ where $L$ is the length of wire

Since $360{}^\circ / 90{}^\circ = 4$, $L = 2\pi r / 4 = \frac{1}{2} \pi r$

$= >$

$$R = \frac{1}{2} \rho \pi r$$ $$R = \frac{1}{2} 3.142 * 2 * 7 = 21.994 \text{ ohm}$$

Answer: the resistance is 22 ohm.