Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
116 views
in General by (106k points)
closed by

Comprehension

The moisture-holding capacity of the soil in a 100-hectare farm is 18 cm/m. The field to be irrigated when 50 percent of the available moisture in the root zone is depleted. The irrigation water is to be supplied by a pump working for 10 hours a day, and water application efficiency is 75%. Details of crops planned for cultivation are as follows

Crop

Root Zone Depth (m)

Peak rate of moisture use (mm/day)

X

1

5.0

Y

0.8

4.0


1. 83 litres/sec
2. 67 litres/sec
3. 57 litres/sec
4. 53 litres/sec

1 Answer

0 votes
by (106k points)
selected by
 
Best answer
Correct Answer - Option 2 : 67 litres/sec

Concept:

The capacity of the pump is given by,

\(Capacity~of ~the~pump= \frac{{{\rm{Volume\;of\;water\;required}}}}{{Working\;time\;of\;pump}}\)

The frequency of irrigation is given by,

\(f_w =\frac{{dw}}{{{C_u}}} \)

dw - Depth of water to be supplied

cu - Daily consumptive use rate

The water application efficiency(η ) is given by

\({\rm{η }} = \frac{{Depth\;of\;water\;stored\;in\;root\;zone}}{{Depth\;of\;water\;applied~to ~soil}}\)

Calculation:

Given:

Area of the irrigation for crop 'X' = 36 hectare

cu = 0.5 cm/day, ηa - 75%

Moisture holding capacity of soil = 18 cm/m × 1 = 18 cm

Allowable depletion of moisture = 50% of available moisture

Allowable depletion of moisture = 0.5 × 18 = 9 cm

Frequency of irrigation crop, \(\frac{{dw}}{{{C_u}}} = \frac{{9}}{0.5} = 18\;days\)

Hence water has to be supplied every 18 days

\({\rm{0.75}} = \frac{{9}}{{Depth\;of\;water\;applied~ to~ soil}}\)

Depth of water applied = 12 cm

Quantity of water required = 0.12 ×  36 × 104 = 43200 m3

\(Capacity ~of~ pump= \frac{{{\rm{43200\times 10^3}}}}{{18\times 10\times 60\times 60}} \)

66.67 litres/sec

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...