Question

18. A body is projected horizontally from a point above the ground. The motion of the body is described by the equations x = 2t and y = 5t2, where x and y are the horizontal and vertical displacements (in m) respectively at time t. What is the magnitude of the velocity of the body 0.2 second after it is projected? (A) 2 ms1 (B) 2 2ms1 (C) 3.5 ms–1 (D) 5 ms–1

Answer 1

Answer:

ANSWER

The horizontal velocity of projectile remains constant throughout the journey.

Since the body is projected horizontally, the initial velocity will be same as horizontal velocity at any point.

Since, x=2t,

dt

dx

=2

∴ Horizontal velocity=2m/s

Initial velocity =2m/s