Question

Water is flowing at the rate of 15 km per hour through a pipe of diameter 14 cm into a rectangular tank which is 50 m long and 44 m wide find the time in which level of water in tank will rise by 21 cm

Answer 1

$\it\huge\mathfrak\red{Answer:-}$]

Let the level of water in the pond rises by 21 cm in t hours.

$\it\huge\mathfrak\red{Given:-:-}$]

Speed of water = 15 km/hr

Diameter of the pipe = 14/100 m

Radius of the pipe (r) = 7/100 m

$\it\huge\mathfrak\red{Solution:-:-}$]

Volume of water flowing out of the pipe in 1 hour

= π r 2 h

= (22/7) x (7/100) x (7/100) x 15000

= 231 m3

Volume of water flowing out of the pipe in t hours = 231 t m3.

Volume of water in the cuboidal pond

= 50 x 44 x (21/100)

= 462 m3

Volume of water flowing out of the pipe

in t hours = Volume of water in the cuboidal pond

So, 231 t = 462

$\huge\boxed{\texttt{\fcolorbox{red}{white}{2 Hours}}}$
$<marquee>$]
Thus, the required time is 2 hours.

Answer 2

In cylinder,

r=7cm=0.7m

l=15km

 =15000m

In tank,

l=50m

b=44m

h=0.21m

Vol.of water in tank=lbh

                               =50*44*0.21

                               =462m³

Height of cylindrical pipe=Vol. / πr²

                                      =462/(0.07)²(22/7)

                                      =462/0.0154

                                      =30000m

Time = 30000/15000

         = 2 hours

Hope that this answer will help you