Question

Water is flowing at the rate of 15km/hour through a pipe of diameter 14cm into a cuboidal pond
which is 50mn long and 44m wide. In what time will the level of water in the pond rise by 21 cm

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Answer 1

Step-by-step explanation:

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

Answer 2

●Solution:-

▪Given that:-

• Water is flowing at the rate of 15km/hour through a pipe

• Diameter of pipe = 14 cm.

• Length and Breadth of cuboidal pond = 50m and 44m.

▪To find:-

• time taken by the level of water in the pond to rise by 21 cm.

______________________________

Let the level of water in the pond rises by 21 cm

in t hours.

Radius of the pipe (r) 7/100 m

Volume of water flowing out of the pipe in 1 hour

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

= 231 m^3

Volume of water flowing out of the pipe in t hours

231t m^3

Volume of water in the cuboidal pond

50 x 44 x (21/100)

= 462 m

Volume of water flowing out of the pipe in t hours =

Volume of water in the cuboidal pond

So, 231 t = 462

t =2

$\therefore$The required time is 2 hours