Question

A cluster of clouds at a height of $1000m$ above the earth burst and enough rain fell to cover an area of ${10}^6{m}^2$ with a depth of $2cm$. How much work has been done in raising water to the height of clouds? (Take $g=9.8m{s}^{-2}$ and density of water = ${10}^{3}kg{m}^{-3}$ )

• A. $1.96\times {10}^{11}J$
• B. $1.96\times {10}^{9}J$
• C. $1.5\times {10}^{11}J$
• D. $2.5\times {10}^{13}J$

Answer 1

The correct option is A $1.96\times {10}^{11}J$

We know,

$W=mgh$

$W=(\rho \times V)gh$

$W={10}^3\times (Area\times Depth)\times 9.8\times 1000J$

$W={10}^3\times {10}^6\times 2\times {10}^{-2}\times 9.8\times {10}^{3}J$

$W=1.96\times {10}^{11}J$