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River problem questions with solutions
Practice Kinematics part-3 Relative motion for JEE Main, JEE Advanced, NEET, and Classes 11–12. Attempt each question, then open it for the full solution.
Showing 1–10 of 43 questions
- MCQmediumKinematics part-3 Relative motion
The downstream drifts of a swimmer crossing a river at equal angular deviations towards downstream and upstream are in the ratio 2:1. The ratio of swimmer speed to current speed cannot be less than:
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JEE MainsNEET
Open question & full solution → - MCQmediumKinematics part-3 Relative motion
River velocity relative to ground is v₀ along +x. A swimmer starts from rest at O and swims perpendicular to the current with acceleration a=2t. Find the equation of the swimmer's trajectory.
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JEE MainsNEET
Open question & full solution → - MCQeasyKinematics part-3 Relative motionOpen question & full solution →
A river of width 120 m flows east at 3 m/s. A boat moves at 5 m/s relative to water. To reach the point directly opposite, it is pointed at angle θ upstream from the perpendicular to the bank. Then:
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- MCQmediumKinematics part-3 Relative motionOpen question & full solution →
A river of width d flows with speed v. A swimmer has speed u relative to water and wants to reach a point B on the opposite bank located L downstream from the point directly opposite his start A. Let S = √(d² + L²). Assuming the target is reachable, the minimum time to reach B is:
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- Multi-correctdifficultKinematics part-3 Relative motion
A river flows at 1 km h⁻¹. A swimmer starts from A and wants to reach C as shown, where AB=BC=400 m. His speed relative to water is 5 km h⁻¹. At what angle θ with the river bank should he swim?
Select all that apply
JEE MainsJEE Advanced
Open question & full solution → - MCQeasyKinematics part-3 Relative motion
A river flows at 9 km/h. A boat moves downstream with speed 27 km/h relative to water. A person in the boat throws a ball vertically upward at 10 m/s. Find the horizontal range of the ball as seen by an observer on the bank. Take g=10 m/s².
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JEE Mains 2025 29 Jan Morning Shift
Open question & full solution → - NumericeasyKinematics part-3 Relative motion
The speed of a swimmer is 4 km h⁻¹ in still water. If the swimmer makes strokes normal to the flow of a river of width 1 km, he reaches a point 750 m downstream on the opposite bank. The speed of river water is ______ km h⁻¹.
JEE Mains31 January 2023Shift 1Morning Shift
Open question & full solution → - MCQeasyKinematics part-3 Relative motionOpen question & full solution →
A river of width 120 m flows east at 3 m/s. A boat can move at 5 m/s relative to water. To cross the river in minimum possible time, the boat should be pointed:
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- MCQmediumKinematics part-3 Relative motion
To cross a river along the shortest path, a swimmer aims at angle θ with the upstream direction. What is the ratio of the minimum possible crossing time to the time taken while crossing along the shortest-distance path? Assume swimmer speed exceeds river speed.
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JEE MainsNEET
Open question & full solution → - MCQeasyKinematics part-3 Relative motionOpen question & full solution →
A swimmer can swim at 5 m/s relative to water. A river flows at 3 m/s and is 80 m wide. The swimmer chooses his direction so that he reaches the point directly opposite. The crossing time is:
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