Why does a shower curtain move in when hot water is running?

Question

If you look at a shower curtain, when the water is not running, it should hang vertically at 90 degrees to the ground. Now, when someone turns on the hot water for a shower, the shower curtain can be seen to want to move inward toward the spray of the water. (This more noticeable the hotter the water is, and if a large stream of water is emanating from the shower head.) Please explain why the shower curtain moves inward using the physics principles from fluid dynamics and thermodynamics.

Thanks for any help! =)

Answer 1

Well the heat (and some water vapor) will travel upward (and at shower temps, pretty quickly). The heat forces air to move upward and, since the curtain is creating a decent "seal", creates a small vacuum that pulls the curtain inward. That's my best guess/understanding. Hope this helps a little

Answer 2

The heat is rising so this creates a vacuum pulling in the curtain.

Answer 3

well becuase heat has sucksion and just like cold things expand. like whenever u put a water bottle in the freezer. it expands so much that sometimes it eventually explodes

Answer 4

The above is correct.  The water heats the air inside the shower.  As we all know heat rises, so the hot air flows upwards in the shower then air needs to move in to replace that air thus sucking the curtain in.