Question

all the passenger sitting in a component of a running train at rest and motion with each other​

Answer 1

They are at rest in reference frame of each other as both have the same velocity that is the velocity of the train .

Answer 2

Answer:

$\huge\underline{\underline{\mathfrak\red{Answer}}}$

they are at rest in reference frame of each other as both have the same velocity that is the velocity of the train .