JEE Main 2025 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 2 April 2025, Shift 1, Physics Q29

Question 29 of 75 in this shift, Physics question 4 of 25, Section A.

A river is flowing from west to east direction with speed of

9\ \mathrm{km\,h^{-1}}

. If a boat capable of moving at a maximum speed of

27\ \mathrm{km\,h^{-1}}

in still water, crosses the river in half a minute, while moving with maximum speed at an angle of

150^\circ

to direction of river flow, then the width of the river is :

(1)112.5 mOfficial answer
(2) $112.5\times\sqrt{3}$ m
(3)75 m
(4)300 m

Official answer

Option 1

NTA final key.

Chapter: Motion in a Plane
Topic: Relative Velocity
Idea tested: River-Boat Minimum Time

Same topic in other shifts

All Relative Velocity questions

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16 Mar 2021, Shift 2 · Q22A swimmer can swim with velocity of 12 km/h in still water. Water flowing in a river has velocity 6 km/h. The direction with respect to…EasyNumerical value
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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.