Question

Consider a large tank filled with water as shown. If a small hole is made at a depth of $10\text{m}$, and the range of water on ground is taken as $R$, Calculate how much extra pressure (in atm) should be applied on water surface so that the range gets tripled. (Assume that 10 m of column of water produces 1atm pressure) (Write upto two digits after the decimal point.)

Answer 1

Range will be thrice only if the speed of the efflux is made thrice the initial value.
Earlier, $v=\sqrt{2gh}$
$\therefore \text{h}$ should become $90\text{m}$
$\Rightarrow$ An extra pressure corresponding to $80\text{m}$ column should be applied.