Question

A cubical vessel of height $1m$ is full of water. What is the amount of work done in pumping water out of the vessel (in $J$)? (Take $g=10m/s^2$)

• A. $1250$
  
• B. $5000$
  
• C. $2500$
  
• D. $1000$
  

Answer 1

The correct option is B $5000$

$W=mgh$ Here $m=v\ast d=Adx\ast d=h^{2}dx\ast 1000$

Therefore $w=h^{2}dx\ast 1000ghAs$ we know that to lift each disc of water present at height x it must be displaced $(h-x)$ Hence by putting the value of x and integrating whole term we get$W=5000J$