KnowledgeBoat Logo

Physics

A body is projected vertically upward with an initial velocity u. If acceleration due to gravity is g, the time for which it remains in air, is —

  1. u/g
  2. ug
  3. 2u/g
  4. u/2g

Laws of Motion

4 Likes

Answer

2u/g

Reason — At the maximum height, v = 0

maximum height = u22g\dfrac{u^2}{2g} (from equation v2 = u2 - 2gh)

time taken by the body to reach the maximum height (t) = ug\dfrac{u}{g} (from equation v = u - gt).

Hence, the same will be the time it takes to get back to the initial point from the highest point. So, total time of journey = 2t = 2ug\dfrac{2u}{g}.

∴ The time for which the body remains in air = 2ug\dfrac{2u}{g}

Answered By

2 Likes


Related Questions