Question

A rectangular tank is 30 m long 20 m broad. Water is being flown into it through a square pipe of side 5 cm. What is the speed of water if the level of water in the tank rises by 1 m in 8 ?

Answer 1

Volume of the water required for rising the water level by 4.5 metre
= 7 × 4 × 4.5 = 126 m3

Time in which the tank needs to be filled = 6 hours and 18 minutes 
=6+1860=6+1860 hr =6+310=6+310 hr =6310=6310 hr

Therefore, amount of water that needs to be supplied by the pipe in 1 hr
126(6310)=126×1063=20126(6310)=126×1063=20 m3/hr

Area of the pipe = 5×4 = 20 cm2 = 0.002 m2

Required speed of the water = 200.002200.002
= 10000 m/hr = 10 km/hr
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