Question

A cylindrical tank of diameter $35$ cm is full of water. If $11$ litres of water is drawn off the water level in the tank will drop by se it [Use $\pi$ = $22/7$]

• A. $11.43$ cm
• B. $114.3$ cm
• C. $1.143$ cm
• D. $0.1143$ cm

Answer 1

The correct option is A $11.43$ cm

Radius of the cylindrical tank = $\frac{35}{2}$ cm
$11$ litres= $11\times 1000c{m}^3=11000c{m}^3$
Let h be the height of the tank,
According to the question, $\pi r^{2}h$ = $11000$
$\Rightarrow \frac{22}{7}\times \frac{35}{2}\times \frac{35}{2}\times h=11000$
$\Rightarrow h=\frac{11000\times 7\times 2\times 2}{22\times 35\times 35}=11.43$ cm. (approx.)
Hence, .Decrease in the water level is $11.43$ cm.