The annual average rainfall in a tropical city is 1000 mm On a particular rainy day (24-hour period)
Q. The annual average rainfall in a tropical city is 1000 mm. On a particular rainy day (24-hour period), the cumulative rainfall experienced by the city is shown in the graph. Over the 24-hour period, 50% of the rainfall falling on a rooftop, which had an obstruction- free area of 50 m2, was harvested into a tank. What is the total volume of water collected in the tank in liters?
| (A) 25,000 | (B) 18,750 | (C) 7,500 | (D) 3,125 |
Ans; 7,500
Sol:
Cumulative rainfall = 300 mm
Area A = 50 m2
50% of the rainfall on a rooftop
Rainfall falling on a rooftop = 50% of cumulative rainfall
The volume of precipitation on rooftop = Area of rooftop × Rainfall falling on a rooftop
Vroof = 50 × 150 × 10-3 = 750 m2 = 7200 liters
The volume of water calculated on tank volume of precipitation on roof loop
VP = 7500 liters
∴ The total volume of water collected in the tank is 7500 liters