Question

water in a canal is 5.4m wide and 1.8m deep,is flowing with a speed of 25km/hr. how much area can it irrigate in 40min, if 10cm of standing water is required for irrigation?

Answer 1

Hi there !!


Breadth , b = 5.4 m

Height[depth] , h = 1.8 m

Speed of canal = 25 km/hr


Length of canal in 1 hour = 25 km


Length of canal in 60 minutes = 25 km                         [ 1 hr = 60 min ]

Length of canal in 1 min = $\frac{25}{60}$

Length of canal in 40 min =   $\frac{25}{60}$ × 40
                                          = 16.67 km [ approx . ]

                                          = 16670 m


Volume of canal =  l b h 

                           = 16670  × 5.4  × 1.8 m
                          
                           = 162032.4 metres

Height of standing water = 10 cm = 0.1 metres


Volume of water in canal = Volume of area irrigated

Volume of area irrigated = Area irrigated × height

162032.4 metres = Area irrigated × 0.1
Area irrigated =   162032.4 ÷ 0.1

                       =  1620324 m²

1m² = 0.0001 hectares 

Area irrigated =  162.0324 hectares

Answer 2

Answer:

Step-by-step explanation:

b=5.4m

h=1.8m

Convert 25km/h into m/min

1250÷3m/min

So we have to find the time in 40 min

1250÷3×40=50000÷3m

l=50000÷3m

Equal the both volume

50000÷3×5.4×1.8=10÷100×l×b

50000×5.4×0.6×100÷10= l×b

50000×54×6×100 ÷ 1000

=10000×162

=1620000cm^2