Question

500 persons took dip in a rectangular tank which is 80 m long and 50 m broad. What is the rise in the level of water(in cm) in the tank, if the average displacement of water by a person is $0.04m^3$?

• A. $0.5$
• B. $1$
• C. $1.5$
• D. $0.25$

Answer 1

The correct option is A $0.5$

Volume of rectangular tank $=l\times b\times h$
$=80\times 50\times h=4000h{m}^3$
(where 'h' is height of tank)
Average displacement of water by a person
$=0.04m^3$
$\therefore$ Average displace of water by 500 person $=0.4\times 500=20m^3$
Rise in water tank $\Rightarrow 4000h=20$
$\Rightarrow h=\frac{1}{200}$
$\Rightarrow h=.005m$
$\Rightarrow h=.005\times 100cm=0.5cm$