Question 269: Current Electricity

Question

Space between two concentric conducting spheres of radii a and b (b > a) is filled with a medium of
resistivity $$\rho $$. The resistance between the two spheres will be :

Accepted Answer

$$R = \int\limits_a^b {{{\rho \,dx} \over {4\pi {x^2}}}} $$
$$ = {\rho  \over {4\pi }}\left( {{1 \over a} - {1 \over b}} \right)$$

Answer

$${\rho  \over {2\pi }}\left( {{1 \over a} + {1 \over b}} \right)$$

Answer

$${\rho  \over {4\pi }}\left( {{1 \over a} + {1 \over b}} \right)$$

Answer

$${\rho  \over {2\pi }}\left( {{1 \over a} - {1 \over b}} \right)$$

Answer

$${\rho  \over {4\pi }}\left( {{1 \over a} - {1 \over b}} \right)$$

Current Electricity

Space between two concentric conducting spheres of radii a and b (b > a) is filled with a medium of resistivity $\rho $. The resistance between the two spheres will be :

Choose the correct answer: