Question

A rectangular tank $30cm\times 20cm\times 12cm$ contains water to a depth of $6cm$. A metal cube of side $10cm$ is placed in the tank with its one face resting on the bottom of the tank. Find the volume of water, in litre, that must be poured into the tank so that the metal cube is just submerged in the water.

• A. $1.4$ litre
• B. $1.3$ litre
• C. $1.2$ litre
• D. $1$ litre

Answer 1

The correct option is A $1.4$ litre

Volume of cubiod$=lbhc{m}^3$
Volume of cube$=edg{e}^3$
$1c{m}^3=1000liter$

height of water
$30\times 20\times h=4600$
$h=7.67cm$
The difference in height when cube submerged in tank$=10-7.67=2.33$
Volume of water that must be poured in tank$=30\times 20\times 2.33=1399.98c{m}^3=1.4litre$