⚛️ Physics · Motion in a Plane · NEET & JEE

A ball is thrown upward from ground. It reaches height 5 m at t=1 s and again at t=3 s. Initial speed is (g=10):

Answer: 20 m/s.

A 15 m/s
B 20 m/s
C 25 m/s
D 30 m/s

Correct answer: B. 20 m/s

Explanation: Ball at 5 m at t=1 and t=3 means midpoint at t=2 (max height). At t=2: v=0, so u=gt=20 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 ball is thrown upward from ground. It reaches height 5 m at t=1 s and again at t=3 s. Initial speed is (g=10):

Concept context

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