When we take the smell of the unlit incense stick, we have to go very close to it. But when we light it and place it in the
corner of the room, its smell spreads everywhere in the room and we no longer have to go near it to take smell. This is
because the particles of the incense stick are mising up with air and as we know that the gaseous molecules move faster,
thus, the smell spreads every where within seconds.