A ball is projected with speed 20 m s -1 at 30 to the horizontal. Its time of flight is (g = 10 m s -2 ):

⚛️ Physics · Motion in a Plane · NEET & JEE

A ball is projected with speed 20 m s<sup>-1</sup> at 30° to the horizontal. Its time of flight is (g = 10 m s<sup>-2</sup>):

Answer: 2 s.

A 1 s
B 2 s
C 3 s
D 4 s

Correct answer: B. 2 s

Explanation: Time of flight = 2u sinθ / g = 2 × 20 × sin30° / 10 = 2 × 20 × 0.5 / 10 = 2 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 projected with speed 20 m s<sup>-1</sup> at 30&deg; to the horizontal. Its time of flight is (g = 10 m s<sup>-2</sup>):

Concept context

More Motion in a Plane questions

A ball is projected with speed 20 m s<sup>-1</sup> at 30° to the horizontal. Its time of flight is (g = 10 m s<sup>-2</sup>):