In the Snyder synthetic unit hydrograph method, the lag time tp (hours) from centroid of rainfall to peak of UH is:
Choose the correct answer
tp = Ct x (L x Lc)^0.3
tp = Ct x (L x Lca)^0.3 (where Ct = basin coefficient, L = main stream length in km, Lca = distance from outlet to point on stream nearest catchment centroid)
tp = peak discharge / area
tp = time of concentration only
Correct Answer
B. tp = Ct x (L x Lca)^0.3 (where Ct = basin coefficient, L = main stream length in km, Lca = distance from outlet to point on stream nearest catchment centroid)
AI Detailed Explanation & IS Code Reference
Unlock the reasoning, formula path and code-linked notes inside your student dashboard.
Snyder UH: tp = Ct(L x Lca)^0.3; qp = Cp x A / tp (Cp = peaking coefficient); peak duration t_R = tp/5.5; T_b (base time) = 3 + tp/8. Ct = 1.35-1.65 (steep), Cp = 0.4-0.8. Synthetic UH is used when no gauge data available for the catchment.
ScoreCardAI links this solution with subject, topic and difficulty signals so your scorecard can identify weak areas after a full mock test.
Practice more Civil Engineering questions
This MCQ belongs to AE Level Premium Test Series. Full tests include timed attempts, rank comparison and subject-wise analysis.