⚛️ Physics · Motion in a Plane · NEET & JEE

A river flows east at 4 m/s. A swimmer swims north at 3 m/s relative to water. His resultant velocity magnitude is:

Answer: 5 m/s.

A 1 m/s
B 5 m/s
C 7 m/s
D 12 m/s

Correct answer: B. 5 m/s

Explanation: Resultant = √(3²+4²) = √(9+16) = √25 = 5 m/s.

Projectile trajectories launched at 15, 30, 45, 60, 75 and 90 degrees at the same speed, each annotated with range R, maximum height H and time of flight T, with coloured dots marking equal time intervals

Projectiles at equal speed: range is maximum at 45°, and complementary angles (30° and 60°) share the same range. Image: Cmglee, CC BY-SA 3.0, via Wikimedia Commons.

Concept context

Vectors, projectile motion, uniform circular motion, and relative velocity - the foundation of 2D kinematics for NEET and JEE.

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A river flows east at 4 m/s. A swimmer swims north at 3 m/s relative to water. His resultant velocity magnitude is:

Concept context

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