If 1 cubic foot of water weighs approximately 62 pounds, what is the weight of a uniform coating of 1 inch of rain over 1 acre of ground?
The correct answer and explanation is:
Correct Answer:
The weight of a uniform coating of 1 inch of rain over 1 acre of ground is approximately 226,512 pounds.
Explanation:
To calculate the total weight of 1 inch of rain over 1 acre, the following steps are used:
Step 1: Convert acre to square feet
1 acre = 43,560 square feet
Step 2: Convert inches to feet
1 inch = 1/12 feet = 0.0833 feet
Step 3: Calculate the volume of water
Volume = Area × Depth
Volume = 43,560 ft² × 0.0833 ft ≈ 3,630 cubic feet
Step 4: Multiply by the weight of water per cubic foot
1 cubic foot of water weighs about 62 pounds
Weight = 3,630 ft³ × 62 lb/ft³ = 225,060 pounds
Using more accurate values for 1/12 (≈ 0.0833333), the volume becomes:
43,560 × 0.0833333 = 3,630 cubic feet (exact)
Then:
3,630 × 62 = 225,060 pounds
If the slight rounding of the weight of water per cubic foot is considered as 62.4 pounds (a more precise value), the weight becomes:
3,630 × 62.4 = 226,512 pounds
So, depending on the precision used, the result can vary slightly. Using the more accurate weight of 62.4 lb/ft³, the final answer is 226,512 pounds.
This calculation shows how rain can represent a massive amount of water and weight. Engineers and meteorologists use this kind of estimation to assess flood risk, soil saturation, and water runoff. Even 1 inch of rain over a large area like an acre carries significant mass, highlighting the importance of proper water drainage and infrastructure during storms or heavy rainfall.