
Applying Bernoulli’s theorem: \(P_1 + \rho g h + \frac{1}{2} \rho v^2 = P_2 + \frac{1}{2} \rho (2v)^2\)
Putting the values, \(4100=800(\frac{3}{2}v^2−10)\)
\(⇒v=\frac{\sqrt{363}}{6}m/s\)


In the first configuration (1) as shown in the figure, four identical charges \( q_0 \) are kept at the corners A, B, C and D of square of side length \( a \). In the second configuration (2), the same charges are shifted to mid points C, E, H, and F of the square. If \( K = \frac{1}{4\pi \epsilon_0} \), the difference between the potential energies of configuration (2) and (1) is given by: