JEE Main20204 Sep 2020Evening ShiftPhysicsMotion in One DimensionActual
A small ball of mass m is thrown upward with velocity u from the ground. The ball experiences a resistive force m k v 2 where v is it speed. The maximum height attained by the ball is :
Options
- A1 2 k tan - 1 k u 2 g
- B1 k ln 1 + k u 2 2 g
- C1 k tan - 1 k u 2 2 g
- D1 2 k ln 1 + k u 2 g
Correct answer
D. 1 2 k ln 1 + k u 2 g
Step-by-step solution
F ne  = ma - mg - mkv 2 = mv dv ds v dv ds = - g - kv 2 - ∫ v 0 0 vdv g + kv 2 = ∫ 0 h ds = h max h max = 1 2 K in g + kv 0 2 g