⚛️ Physics · Motion in a Plane · NEET & JEE

Two balls are thrown simultaneously: one vertically up at 20 m/s, one dropped from 80 m height. When do they meet? (g=10 m/s²)

Answer: 4 s.

A 2 s
B 3 s
C 4 s
D 5 s

Correct answer: C. 4 s

Explanation: Ball 1: y1=20t-5t². Ball 2: y2=80-5t². Meeting: y1=y2 → 20t=80 → t=4 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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Two balls are thrown simultaneously: one vertically up at 20 m/s, one dropped from 80 m height. When do they meet? (g=10 m/s²)

Concept context

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