Can they move physical objects?
Angelic beings are powerful spiritual creatures and have limited power when it comes to physical matter. Most of the time demons perform visual tricks by negatively influencing our minds with illusions, making it appear that something is moving when it is in fact not.
Other times they can move physical objects, making them fly across the room as can be seen in various horror movies. It is a rare occurrence, but can happen. Thomas Aquinas devotes a question in his Summa explaining how this can happen.