What would you learn in a week in school?

[veggiechicken]

Thanks Mothhawk. So I can ignore litres on compost bags and call it kilos instead!
56 litres = 56 kg = 123.3 lbs = 8.8 stone.
I can't believe that I can lift (just) something that is almost my weight (give or take a stone) assuming its dry
Don't think I'll enter the Strongest woman competition though!

[bearded bloke]

Kilo's & Litre's are not the same Mothhawk,kilo is a measure of weight & litre is a measure of volume.
VC,compost is measured in litres for the above reason,any bag can physically contain a known volume,the holes are there to allow the evaporation of moisture that is contained in the compost at the packing stage,hence why the contents are always marked as "when packed",the actual weight of a bag of compost is variable depending on the density of it's component parts.

[veggiechicken]

Oh No, BB Just when I think I understand, it all goes compost shaped!
There was I, thinking how strong I am for an old biddy and now, I'll probably find it weighed the equivalent of 3 bags of sugar

[bearded bloke]

If anyone wants to learn imperial dimension,weights,etc go to America where it is still the preferred system.

But do take care as American liquid measures have the same names as UK but the volumes are different,similarly until comparatively the Metre varied in length between various European countries

[bearded bloke]

Oh No, BB Just when I think I understand, it all goes compost shaped!
There was I, thinking how strong I am for an old biddy and now, I'll probably find it weighed the equivalent of 3 bags of sugar

Soz VC,If you assume everything is bagged to the same volume of 60 litres,most people on the planet could lift a bag polystyrene,but you would need a well built person to lift the same volume of mercury

[binley100]

My head hurts...........

[veggiechicken]

Why, oh why, can't there be a universal measuring system? I thought that metrication was meant to be simpler, and Units of 10 are more straightforward but why am I so confused, years after we adopted it.(and do I care - Nah!!!)

[veggiechicken]

Soz VC,If you assume everything is bagged to the same volume of 60 litres,most people on the planet could lift a bag polystyrene,but you would need a well built person to lift the same volume of mercury

And that is exactly my problem. How do I know how much compost I'm buying. It could be fluffy stuff, bulked up with moisture retaining granules or vermiculite, just to fill the bag. Also the 56 litre bags aren't full to the brim so how do I know I'm not being ripped off! Its all a big con, I reckon.

[bearded bloke]

metrication was meant to be simpler, and Units of 10 are more straightforward but why am I so confused, years after we adopted it.

Because we tend to try & convert everything backwards into the system that we are most comfortable with.
For engineering I like to work in imperial.example I am quite happy that there are 39.3 thousandths of an inch in a millimetre (near as)but when working in metric 39.3 microns is 1.5 thou' (near as),yet for building work I find metric easier to work in

[bearded bloke]

56 litre bags aren't full to the brim

That is to be expected,read the bag & it will say 56 litre when packed,when packed is the salient wording.If it has been stored in a warm &/or dry place there will be loss of volume by evaporation of moisture,where if it is stored outside in the rain the volume will increase by water intake through the bag ventilation holes.

[bearded bloke]

Another point to think on here (not immediately obvious) is that you will get far better growth from plants in compost that has been stored undercover,this is simply because every-time the bag gets wetted by rainfall into the topside ventilation holes nutrients are washed out of the underside ventilation holes.

[binley100]

So ............buy the bag from the bottom of the pile ..

[veggiechicken]

So buying compost is like the old frozen chicken con. The chicken is injected with water, and weighed, and priced accordingly. When defrosted the chicken weighs much less. Or the frozen prawn scam where each prawn is coated with an ice glaze, (to keep it from sticking to another prawn) and packed. When defrosted, there's may be only half the weight of prawns you thought you'd bought.
So, in compost terms, the bags are packed with loose fluffy stuff (it could even be aerated if you were an experienced con-compost merchant). This settles in the bag and the volume is reduced, but water could be introduced to add weight to convince you that you'd bought a full bag.
I'm just naturally suspicious

[mrbadexample]

kilo is a measure of weight

Actually, it's a unit of mass.

Weight is the force exerted by gravity on an object.
Mass is a measure of how an object resists inertia.

An object with mass of 1kg will weigh less on the moon than on Earth, as the force exerted by gravity is less. Since veggiechicken is clearly not on the same planet as the rest of us, this is a significant point.

[veggiechicken]

Now you've completely thrown me MBE. So if I buy my 56 litres of compost on the moon it will weigh less than if I bought it on Earth - and, more to the point, if I lived on the moon, my Body Mass Index would be just right and I wouldn't be overweight.
When's the next shuttle?