Question

why is it advised to tie a rope on the luggage while you travel by the bus

Answer 1

It is because of inertia of motion because due to inertia of motion the luggage may be fall so there os necessary to tie a rope on the luggage

Answer 2

so that the luggage bag doesn't open up or it doesn't fall down... also it becomes difficult for thieves to steal anything from the bag.

hope it helps u