Bottle Holes Stop When Capped

Water flow slows/stops when air cannot enter. Ask students to predict what will happen. Let water stream with cap loose, then tighten cap. Key idea: Air must replace leaving water; sealed pressure drops inside. Ask: Why does the cap change the holes at the bottom? Safety and cleanup: Teacher prepares holes; use tray. https://www.google.com/search?q=%22Bottle+Holes+Stop+When+Capped%22+science+demonstration+experiment