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        general >> truth >> How is the capacity arrived at
        
(Message started by: ragtlll on Mar 6^th, 2014, 1:39pm)

Title: How is the capacity arrived at
Post by ragtlll on Mar 6^th, 2014, 1:39pm

what would the equation be to determine the capacity of a trash bag?

Let me clarify. I have many different trash bags to consider such as can be found here interplas.com/trash-bags. The issue I have is that the website states the certain gallon capacity of the trash bags but what about when the trash bag is tied to constrain the contents. Of course, this presents a dilemma because where would the trash bag be tied and what if I want to find the EXACT millimeter capacity of even the largest capacity bag?

Title: Re: How is the capacity arrived at
Post by towr on Mar 6^th, 2014, 10:07pm

It would be very complicated, because it's a complicated shape.
If you approximate it by a cylinder, it's height * radius squared * pi.

Title: Re: How is the capacity arrived at
Post by JiNbOtAk on Mar 6^th, 2014, 11:42pm

I prefer the Edison's approach. Fill up the trash bag with water, weigh the filled bag and obtain the volume. Much easier than attempting numerous multiple integral. :P

Title: Re: How is the capacity arrived at
Post by towr on Mar 7^th, 2014, 4:56am

But we're asked for an equation. So perhaps, [flow of water in L/s] * [time till bag fills up in s] :P

Title: Re: How is the capacity arrived at
Post by rloginunix on Mar 7^th, 2014, 8:38am

And you could improve the answer by one molecule by replacing water with air - cheapening the test, increasing the chances of the trash bag test survival and measuring the flow in convenient cubic units.

On a separate note, if you have a stopwatch and know the flow generated by your lungs that's all you need to do the estimate yourself.

Title: Re: How is the capacity arrived at
Post by Grimbal on Mar 11^th, 2014, 8:01am

Not to mention that when you buy a bag, the volume is usually written on the label.
Or you can ask the salesman.

Title: Re: How is the capacity arrived at
Post by movie4fun on Aug 18^th, 2014, 7:14pm

you have to consider the type of trash you are gonna putin there.