Question

State newtons first law of motion and explain why is itadvised to tie any luggage kept on the roof of a bus with rope

Answer 1

Newton's first law of motion states that:

the body is at rest or in uniform motion untill and unless an external force is applied on it.

When the bus stops suddenly, the luggage on the roof top will fall forward due to inertia of motion. Similarly when the bus starts the luggage will fall backwards due to inertia of rest. To avoid this, any luggage kept on the roof of a bus is tied with a rope.