A railway compartments is `16 m` long, `2.4 m` wide and `3.2 m` high. It is moving with a velocity `v` A particle moving horizontally with a speed `u` perpendicular to the direction of `v` enters through a hole at an upper corner `A` and strikes the diagonally opposite corner `B`.Assume `g=10 m//s^(2)`.

Options

A. `v=20 m//s`
B. `u=3 m//s`
C. To an observer inside the compartment, the path of the particle is a parabola
D. To a stationary observer outside the compartment, the path of the particle is parabola

Answer

A, B, C, D

Explanation

(a,b,c,d) consider the vertical motion of the particle after entering the compartment.Let it reach the floor in time `t`
`3.2=1/2(10)t^(2) , or t=0.8s`
Due to the velocity component `u`,which remain costant, it covers a distance of `2.4 m` in `0.8 s`
`u=(2.4m)/(0.8s)=3m//s` Also `v=(16m)/(0.8)=20m//s`