Question for the mathematicians - how to work out plastic bag litre size?
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Soldato
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-edit typed into calculator incorrectly!
Volume in metres.
1000L in 1m3
so 0.2773125 m3
277 Litres
I think
Volume in metres.
1000L in 1m3
so 0.2773125 m3
277 Litres
I think
Last edited:
^might not be 100% accurate if its got a pinched bottom...
Is it strong enough to fill with water? or if not put it into a larger container that is strong enough, fill the bag up, then drain it and see how much water its holding.
Is it strong enough to fill with water? or if not put it into a larger container that is strong enough, fill the bag up, then drain it and see how much water its holding.
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Soldato
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save up a load of 2l bottles.
fill them with water.
pour into bag until full.
probably it can't hold many litres before it breaks.
#forscience
fill them with water.
pour into bag until full.
probably it can't hold many litres before it breaks.
#forscience
Last edited:
Soldato
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could do the experiment with the bag in water
Irregular shapes are always tricky, yet bin bags generally give the capacity in litres plus the dimensions. Might that be a way to guestimate this?
Take some small bin bags (compost ones?), blow them up with air, close them and see how many it takes to fill them?
As already said, water-filling requires a very strong bag. Air-filling would not but air is harder to measure (remember 1 litre of water is 1kg (at 4°C etc.)).
Submersing the bag to see the amount of water it can be displace requires some very big water containers and since we are talking about displacing ~270 litres there would still be a lot of force involved. However displacement & submersion has the advantage that it can work gradually so as long as the bag was airtight enough the full 270kg of displaced water would never have to be applied all at once, but at the end you are still displacing 270kg which is asking a lot (too much) from a plastic bag.
Guess if you wanted to measure a balloon you'd make a cast and burst the balloon. A lot of work but probably the most accurate thing to do.
Take some small bin bags (compost ones?), blow them up with air, close them and see how many it takes to fill them?
As already said, water-filling requires a very strong bag. Air-filling would not but air is harder to measure (remember 1 litre of water is 1kg (at 4°C etc.)).
Submersing the bag to see the amount of water it can be displace requires some very big water containers and since we are talking about displacing ~270 litres there would still be a lot of force involved. However displacement & submersion has the advantage that it can work gradually so as long as the bag was airtight enough the full 270kg of displaced water would never have to be applied all at once, but at the end you are still displacing 270kg which is asking a lot (too much) from a plastic bag.
Guess if you wanted to measure a balloon you'd make a cast and burst the balloon. A lot of work but probably the most accurate thing to do.
Last edited:
Soldato
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Why do you need to know the capacity of the bag ? Can't you just use multiple bags if this one isn't enough ?
Put the bag into a dustbin /wheely bin?
Soldato
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WTF is this thread about????