⚛️ Physics · Motion in a Plane · NEET & JEE

Displacement of a particle is x = t³ - 3t + 2. When is the particle momentarily at rest?

Answer: t=1 s.

A t=0 s
B t=1 s
C t=2 s
D t=3 s

Correct answer: B. t=1 s

Explanation: v = dx/dt = 3t²-3. v=0 when 3t²=3, t²=1, t=1 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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Displacement of a particle is x = t³ - 3t + 2. When is the particle momentarily at rest?

Concept context

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