a
(a)Let \(A = \) cross-section of tank
\(a = \) cross-section hole
\(V =\) velocity with which level decreases
\(v = \) velocity of efflux
From equation of continuity \(av = AV \Rightarrow V = \frac{{av}}{A}\)
By using Bernoulli's theorem for energy per unit volume
Energy per unit volume at point A
= Energy per unit volume at point B
\(P + \rho gh + \frac{1}{2}\rho {V^2} = P + 0 + \frac{1}{2}\rho {v^2}\)
==> \({v^2} = \frac{{2gh}}{{1 - {{\left( {\frac{a}{A}} \right)}^2}}} = \frac{{2 \times 10 \times (3 - 0.525)}}{{1 - {{(0.1)}^2}}} = 50{(m/\sec )^2}\)
