I was asked to bring something into class with a pressure less than 1.0 atm, after researching i found out that if I heated a bottle it will shrink and therefore this bottle will have the needed pressure. the problem is that after I put the bottle inside the microwave for 1 or 2 minutes nothing happened to it. so today i got to school and one of my teachers just crushed the bottle and put the cap in itand say it had less than 1atm is this right?
Yes. If you place a plastic bottle in the microwave, it didn't get much heat. Neither air nor plastic absorbs much in the way of microwaves in an oven; therefore, you had no heating. What the teacher did was to push the air OUT of the bottle, while holding the bottle crimped then the teacher placed the cap back on, the air can't get back IN, so there is less than 1 atm pressure in the bottle. Clever, huh?
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