NTA Abhyas JEE Main2020PhysicsMotion in Two DimensionsPractice
A ball is thrown with a speed u , at an angle θ with the horizontal. At the highest point of its motion, the strength of gravity is somehow doubled. Taking this change into account, the total time of flight of the projectile is
Options
- A2 u s i n θ g
- B3 2 u s i n θ g
- C3 4 u s i n θ g
- D2 + 1 2 u s i n θ g
Correct answer
D. 2 + 1 2 u s i n θ g
Step-by-step solution
Time of ascent t 1 = u s i n θ g Time of descent t 2 = 2 H 2 g t 2 = u 2 s i n 2 θ 2 g 2 = u s i n θ 2 g t = t 1 + t 2 = u s i n θ g + u s i n θ 2 g ⇒ u s i n θ g 2 + 1 2