Select the correct option for the given statements. Statement 1: Runoff is a function of precipitation, intensity, duration and its coverage. Statement 2: The size of catchment has a definite effect on the runoff. More the area, lesser will be the runoff.
- AStatement 1 is false and statement 2 is true
- BBoth statement 1 and statement 2 are true
- CStatement 1 is true and statement 2 is falseCorrect
- DBoth statement 1 and statement 2 are false
Solution
Concept
Runoff depends on rainfall characteristics (intensity, duration, areal coverage). A larger catchment gives more total runoff.
Step-by-step solution
1. Statement 1: runoff depends on the intensity, duration and areal spread of precipitation. This is true. 2. Statement 2: a larger catchment collects rain from more area, so total runoff volume increases. 3. So the claim 'more area, lesser runoff' is false. 4. Statement 1 is true and Statement 2 is false. Answer (C).
Explanation
Rainfall intensity, duration and coverage directly control how much water runs off, so Statement 1 is true. A bigger catchment gives more total runoff, not less, so Statement 2 is false.
Why the other options are wrong
(A) wrongly calls Statement 1 false. (B) wrongly accepts Statement 2. (D) wrongly rejects Statement 1.
Shortcut
Bigger catchment means more total water collected.
Common mistake
Confusing total runoff (which increases with area) with peak runoff per unit area (which decreases with area).
Correct answer: C) Statement 1 is true and statement 2 is false