Pressure

[shawngill]

A jar of Sweet and Sour sauce has a lid with a small circular "button" at its centre. The printing on the lid reads "Safety Button: pops up when original seal is broken".
Explain (1) why the button remains pushed in when the seal is intact and
(2) why this warning is necessary

[Big Bri]

vacuum pressure .to prove that the lid as not been opened or tampered with

[squarebear]

No need for the insults Bri, not everyone shares the same knowledge. What is obvious for some may not be for others.

[buildersmate]

Its only a kid with homework he can't be bothered to research. Look at the way the question is copied out.

[bigmamma]

shawngill , perhaps a please or thankyou wouldn't go amiss love eh?