Air pressure must have something to do with it

Instead of a door, I hang a sheet inside the doorframe of a small bedroom. The sheet completely covers the doorframe, like a normal door would.

When the building's central heating turns on, the sheet billows inward into the room, and when the heating turns off, the sheet billows outward out of the room.

This seems to be counterintuitive, as one might expect the bedroom's heating to push the sheet out, but instead it is being pushed in.

Why is this?

#Mechanics

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Comments

May be it is not because of the pressure difference rather only the temperature difference of the two faces of the sheet. The inner face becomes hot and tries to expand while the outer face tries to contract. This result in a bulge Top view

Rohit Gupta - 3 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$