Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Boat and StreamModerate · 45s
With u = 13 km/h and v = 3 km/h, a boat goes downstream for 2.5 h and upstream for 3 h. What is the net displacement from the start?
TopicBoat and Stream
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Down distance = (u+v)*2.5 = 40.0 km; Up distance = (u-v)*3 = 30 km; Net = 10.0 km downstream.
Final Answer: Option A — 10 km