回る and 回す: rotation and passing things around
Compare an object rotating with someone turning it, then examine visiting several places and passing material around.
What rotates and who turns it
風で風車が回っています。 says that a windmill is turning in the wind. With 回る, read まわる, the rotating object is the subject.
ハンドルを右に回してください。 asks someone to turn the handle or wheel to the right. 回す, read まわす, marks the object turned with を.
Visit several places
休日に三つの店を回りました。 says that someone visited three shops on a day off. It describes visiting places rather than spinning in one spot.
係の人が教室を回って、忘れ物を確認しました。 says that an attendant went around the classrooms checking for forgotten belongings. The places with を form the area visited.
Pass something along
資料を読んだら、隣の人に回してください。 asks someone to pass the material to the next person after reading it. 回す can mean passing something along as well as rotating it.
全員に資料が回りました。 says that the material reached everyone in turn. 回った does not establish that everyone read or agreed with it.
Does 資料を隣の人に回す mean rotating the paper?
Show the answer and why
Here it means passing the material to the next person. に marks the recipient, giving the verb a passing-on sense.