Question
A particle is projected with velocity 
at such an angle that it just clears two walls of equal height h which are at a distance 2h from each other. Show that time of passing between the two walls is 
Solution
Given,
Velocity with which the particle is projected = 2
Height of the wall = h
Distance between the walls = 2h
Let the particle be projected at angle θ.
Velocity with which the particle is projected = 2
Height of the wall = h
Distance between the walls = 2h
Let the particle be projected at angle θ.
Time taken by particle to cross the two walls each of height 'h' is equal to difference of instants when it would be at a height h above ground.
The kinematics of motion of particle in vertical direction is given by,
That is,
is the time of passing between the two walls.
The kinematics of motion of particle in vertical direction is given by,
That is,
is the time of passing between the two walls. 
