My experiment failed

The experiment I am discussing here is one of the common ones.When we take glass filled with water and keep a postcard on the mouth of the glass,pressing it.And then suddenly reverse the glass along with the card pressing with our hand and then release the postcard free,it remains attached to the glass and the water inside the glass does not falls.But after leaving for sometime the postcard finally falls.Why is it so?

#ClassicalPhysics

Easy Math Editor

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Comments

I think it may not be the answer, but here is what i thought it could be.

Its probably because your postcard had soaked some water , which would have resulted in leakage of water from glass which instantly decrease the pressure between your postcard and glass and so it loses the grip.

Rajat Bisht - 6 years, 1 month ago

Sorry ,but I did not understand the meaning of the last line that is the decrease in pressure between the postcard and glass:)

Siddharth Singh - 6 years, 1 month 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}`	$\boxed{123}$