Particles `P` and `Q` of mass `20 gm` and `40 gm`respectively are simultaneously projected from points `A` and `B` on the ground . The initial velocities of `P` and `Q` make ` 45(@)` and `135(@) ` angles respectively with the horizontal `AB` as shown in the figure . Each particle has an initial speed of `49 m//s`. The separation `AB` is `245 m `. Both Particle travel in the same vertical plane and undergo a collision . After the collison , `P` retraces its path , Determine the position of `Q` when it hits the ground . How much time after the collision does the particle `Q` take to reach the ground ? Take ` g = 9.8 m//s^(2)`.

Particles `P` and `Q` of mass `20 gm` and `40 gm`respectively are simu

1.	Particles `P` and `Q` of mass `20 gm` and `40 gm`respectively are simultaneously projected from points `A` and `B` on the ground . The initial velocities of `P` and `Q` make ` 45(@)` and `135(@) ` angles respectively with the horizontal `AB` as shown in the figure . Each particle has an initial speed of `49 m//s`. The separation `AB` is `245 m `. Both Particle travel in the same vertical plane and undergo a collision . After the collison , `P` retraces its path , Determine the position of `Q` when it hits the ground . How much time after the collision does the particle `Q` take to reach the ground ? Take ` g = 9.8 m//s^(2)`.
Answer» Correct Answer - A::B::C::D If a body drops from a height `H` above the ground then the time taken by it to reach the ground ` t = sqrt ((2H)/(g)) :. t = sqrt (( 2xx61.25)/(9.8)) = 3.53 s `