Water in a canal, 30 dm wide and 12 dm deep is flowing with velocity of 10 km/hr. How much area will

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27 Apr 2016 Area

Water in a canal, 30 dm wide and 12 dm deep is flowing with velocity of 10 km/hr. How much area will it irrigate in 30 minutes, if 8 cm of standing water is required for irrigation?

OPtion

1) 425000 m^2
2) 4.25 km^2
3) 0.4 km^2
4) 275000 m^2
5) 1.8 km^2
6) 225000 m^2
7) 235500 m^2
8) 4000000 m^2
9) 180000 m^2
10)40 k^2

Solution

Width of the canal = 30 dm = 300 cm = 3 m
Depth of the canal 12 cm = 120 cm = 1.2 m
It is given that the water is flowing with velocity 10 km/hr
Therefore Length of the water column formed is 1/2 hour = 5 km = 5000 m
Therefore volume of the water flowing in 1 hour
= Volume of the cuboid of length 5000 m, width 3 m and depth 1.2 m
=> Volume of the water in half hour = (5000*3*1.2) m^3 = 18000 m^3
Suppose x m^2 area is irrigated in 1/2 hour
x*8/100 = 18000
x = 1800000/8
x = 225000
Hence the canal irrigated 225000 m^2 area in 1/2 hours
Option 6)

Correct Option: 6 Best Solution (15)

sumant kumar   8 years AGO

width of canal=30dm = 3 m
depth of canal = 12dm = 1.2m
rate of flow of water= 10 km /hr
length of water column in 30min= 1/2 * 10 KM
= 5KM= 5000M
VOLUME of water flown in 30min= 3m * 1.2m * 5000m
= 18000m^3
8cm= .08m standing water is required
therefor,
area in 30min= volume/height
=18000/0.8
= 225000m^2

Like? Yes (20) | No (3)  

ABHINAV PUSHPAM   8 years AGO

Given width of the canal = 30 dm = 300 cm
Depth of canal = 12 dm = 120 cm
Rate of flow of water = 10 km/hr
Distance covered by the water that will flow in 30 minutes = 10*30/60
= 500000 cm
Amount of water irrigated in 30 minutes =300 × 120 × 500000
= 1800000000 cu cm
Area irrigated if 8cm standing water is desired = (1800000000/8)
= 2250000000 sq cm

= 225000 sq m
Option 6)

Like? Yes (7) | No (3)  

Maji   8 years AGO

wide= 3m.
depth= 1.2m.
velocity= 10,000m/h.
length of water column if flow of water in 30 min= 10,000*(30/60).
=5,000.
amt of water irrigated in 30 min
=30*12*5000,
=18,00,000.
area irrigated in 30 min if 8cm of standing water is required=1800000/8
= 225000 m^2.

Like? Yes (7) | No (3)  

prafull   8 years AGO

h= 300 cm
w=120cm
distance covered in 30 mins = (10*1/2) = 5km = 500000cm
area covered in 30 mins = 500000*300*120/8 = 225000 m^2

Like? Yes (6) | No (5)  

PIYUSH KUMAR   8 years AGO

wide =30 dm = 300cm
deep =12 dm = 120cm
distance cover by water in 30 Min =10*30/60 = 5 Km = 500000
Amt water irrigate in 30 min is 300*120*500000
= 1800000000 cub cm
Standing water desire is 1800000000/8 =2250 000 000sqr cm
now in m 2250000 m^2
option is 6

Like? Yes (2) | No (3)  

Lenin   8 years AGO

flow rate, Q = AxV = (3x1.2) 10000= 36000 m^3/hr.
for 30 minutes the discharge = 18000 m^3
so the area = volume / depth = 18000 / 0.08 = 225000 m^2.
the answer is option 6.

Like? Yes (3) | No (4)  

MRITUNJAY   8 years AGO

Given width of the canal = 30 dm = 300 cm
Depth of canal = 12 dm = 120 cm
Rate of flow of water = 10 km/hr
Distance covered by the water that will flow in 30 minutes = 10*30/60
= 500000 cm
Amount of water irrigated in 30 minutes =300 × 120 × 500000
= 1800000000 cu cm
Area irrigated if 8cm standing water is desired = (1800000000/8)
= 2250000000 sq cm

= 225000 sq m
Option 6)

Like? Yes (2) | No (4)  

abhishek chaubey   8 years AGO

first of all change every length unit to cm.
now width of the canal=30dm=300cm
depth of canal=12dm=120cm
now rate of flow of water=10km/h
so distance covered by water in canal that will flow in 30 minutes= 10*30/60= 5km = 500000 cm
now total amount of water consumed in irrigation during these 30 minutes= l*b*h
= 500000*300*120 =18000000000 cubic cm
now 8 cm standing water is required.
so total irrigated area= 18000000000/8 (volume/length)
=2250000000 square cm =225000 square meter
=225000 m^2

Like? Yes (2) | No (4)  

Divesh Singla   8 years AGO

Given width of the canal = 30 dm = 300 cm
Depth of canal = 12 dm = 120 cm
Rate of flow of water = 10 km/hr
Distance covered by the water that will flow in 30 minutes
= 500000 cm
Amount of water irrigated in 30 minutes =300 × 120 × 500000
= 1800000000 cu cm
Area irrigated if 8 cm standing water is desired = (18000000000/8)
= 2250000000 sq cm/10000=225000m^2

Like? Yes (2) | No (4)  

Jaikumar Bhatia   8 years AGO

Width of canal=30dm=3m
Depth of canal=12dm=1.2m
Rate of flow of water=10km/hr=10,000m/hr
Distance covered by water that flow in 30 minutes=10*(30/60)
=>5km=5000m
Amount of water irrigated in 30 minutes
=3*1.2*5000=18000m^3
Area(a) irrigated if 8cm(0.08m) standing water desired
a*0.08=18000
a=225000m^2
Ans: area irrigated is 225000m^2
Option is (6)

Like? Yes (3) | No (5)  

Akshat Sood   8 years AGO

Given width of the canal = 30 dm = 300 cm
Depth of canal = 12 dm = 120 cm
Rate of flow of water = 10 km/hr
Distance covered by the water that will flow in 30 minutes (10*30/60)
= 500000 cm
Amount of water irrigated in 30 minutes =300 × 120 × 500000
= 18*10^9 cu cm
Area irrigated if 8 cm standing water is required = (18*10^9/8)
= 225*10^7 cm²
=225000m²

Like? Yes (1) | No (3)  

RAHUL KUMAR   8 years AGO

Given width of the canal = 30 dm = 300 cm

Depth of canal = 12 dm = 120 cm

Rate of flow of water = 10 km/hr

Distance covered by the water that
will flow in 30 minutes = 10*30/60 = 5 Km = 500000 cm

Amount of water irrigated in 30
minutes =300 × 120 × 500000 = 18000000000 cu cm

Area irrigated if 8 cm standing
water is desired = (18000000000/8) = 2250000000 sq cm = 225000 m^2

option (6)

Like? Yes (2) | No (5)  

rydham goyal   8 years AGO

given
width d of canal = 30 dm = 300 cm = 3 m
( since 1 dm = 10 cm and 100 cm = 1 m)

depth of canal = 12 dm = 120 cm = 1.2 m

given velocity of water = 10 km/hr

therefore , length of water canal formed in 1/2 hours = 10 * 1/2 = 5 km = 5000 m

hence volume of water flowing in 1/2 hour = volume of canal = 5000 * 1.2 * 3
= 18000 m^3

let the area cultivate by water is A^2 m^2
therefore
A^2 * 8cm = 18000 m^3
A^2 * 8/100 = 18000
A^2 = 18000 * 100/8
A^2 = 225000 m^2

therefore area irrigated by the canal is 225000 m^2

Like? Yes (2) | No (5)  

Nandkishor jaiswal   8 years AGO

from the equation,
3*1.2*5000 = 8/100 * a (10 dm = 1m and a is area)
so, a= 225000m^2

Like? Yes (3) | No (7)  

Sweta Mallick   8 years AGO

amount of water in 30 min is 1.2*3*5000*10000/2=18000m^3
the area is=18000/.08=22500m^2.here 8cm standing water is required

Like? Yes (1) | No (5)