Calculate the Quantity of Spray Solution Required per Hectare
Question: The quantity of water taken in a hand-operated knapsack sprayer is 10 litres. After spraying an area of 40 m², the remaining water in the tank is 8 litres. Find the quantity of water solution required to cover one hectare of field.
Solution
Given:
- Initial quantity of water (V₁) = 10 litres
- Remaining quantity of water (V₂) = 8 litres
- Area sprayed (A) = 40 m²
- One hectare = 10,000 m²
Formula:
Spray solution required (litres/ha) = [(V₁ − V₂) / A] × 10,000
Calculation:
= [(10 − 8) / 40] × 10,000
= (2 / 40) × 10,000
= 500 litres/ha
Final Answer
The quantity of spray solution required to cover one hectare is 500 litres.
Calculate Area Coverage and Time Required for Spraying
Question: A person walks at a speed of one kilometre per hour while covering a swath of 0.5 m wide. How much area will be covered in one hour? Calculate the time required to spray one hectare.
Solution
Given:
- Walking speed = 1 km/hour
- Swath width = 0.5 m
- One kilometre = 1,000 metres
- One hectare = 10,000 m²
Step 1: Calculate the area covered per hour.
Formula:
Area covered (ha/hr) = (Walking speed (m/hr) × Swath width (m)) / 10,000
Area covered = (1,000 × 0.5) / 10,000
= 500 / 10,000
= 0.05 ha/hr
Converting into square metres:
0.05 × 10,000 = 500 m²/hr
Step 2: Calculate the time required to cover one hectare.
Time required = Total area / Area covered per hour
= 1 / 0.05
= 20 hours
Final Answer
- Area covered in one hour = 500 m²
- Time required to cover one hectare = 20 hours