- The electric field inside a uniformly charged spherical shell is 0 (Coulomb’s Law), hence \( {(A)-(III)} \).
- The electric field due to a uniformly charged infinite plane sheet is \( \frac{\sigma}{2\epsilon_0} \), hence \( {(B)-(II)} \).
- The electric field outside a uniformly charged spherical shell behaves like that of a point charge and is \( \frac{\sigma}{\epsilon_0 r^2} \), hence \( {(C)-(IV)} \).
- The electric field between two oppositely charged infinite plane sheets is \( \frac{\sigma}{\epsilon_0} \), hence \( {(D)-(I)} \). Thus, the correct answer is \( {(1)} \).
A string of length \( L \) is fixed at one end and carries a mass of \( M \) at the other end. The mass makes \( \frac{3}{\pi} \) rotations per second about the vertical axis passing through the end of the string as shown. The tension in the string is ________________ ML.
Let $ P_n = \alpha^n + \beta^n $, $ n \in \mathbb{N} $. If $ P_{10} = 123,\ P_9 = 76,\ P_8 = 47 $ and $ P_1 = 1 $, then the quadratic equation having roots $ \alpha $ and $ \frac{1}{\beta} $ is: