Ron came out of the Gryffindor common room busy in thought. He wasnt necessarily thinking about one thing but actually a couple. For instance, he was wondering where Harry was, he hadnt seen him in a long time. Or he was wondering what was for dinner tonight in the great hall. Not that it mattered since Ron would eat anything they put in front of him. But because he was so lost in thought, he wasnt really paying attention to what was ahead of him.
'I wonder if muggles have flying brooms but they just dont know it,' Ron thought, ' I mean, what if a muggle started sweeping with a Cleansweep. Would anything happen?'
As Ron was thinking this, he accidently bumped into someone, knocking them to the floor and sending their books flying everywhere. "Er, sorry" Ron said as he bent down to help pick up the books.