Homework Help

[StarsOfCCTV]

Ignore above post Defra sorted the problem

Basically just wondered if there was any more I'm missing from the below?
Methods of separating products. I have got suction filtration, filtration and distillation.

Ways of reducing the cost of materials, I have got buy in bulk and re-use/recycle.

[Abigail]

Four ways of separating things: distillation, filtration, evaporation, condensation.

Reducing costs: economies of scale, different supplier, buy direct from the manufacturer, imports, buy online.

[Kim]

Fractional Distillation? Don't know if that just comes under distillation but as you have two types of filtration there I thought I'd post it.

And for the materials one, use materials that you/family members/friends already have so you don't have to buy in as much. That's what we did in YE anyway

[StarsOfCCTV]

Thanks you two, great suggestions I can use.

[Abigail]

I'm writing an assignment on the Macpherson report. Should I reference this as a book? It's a report really but I can't find a way of referencing a report using Harvard.

[di marco]

I'm writing an assignment on the Macpherson report. Should I reference this as a book? It's a report really but I can't find a way of referencing a report using Harvard.

i would think so. i have to use the harvard system as well, in our student handbook it lists how to properly reference different sources. if you still need to know, ill look it up for you and see if it says anything about reports

[StarsOfCCTV]

So....does anyone know anything about U-values?

I need to do some calculations for my physics. Its about thermal insulation any idea on types of calculations? I've tried searching but nothing that makes sense so far...

[Abbie]

This might sound silly but is U-values got anything to do with a Stats test?

[StarsOfCCTV]

Kind of...I have this so far

For the basic calculation..
Heat loss
Side/Inside of insulation box: Loft insulation experiment
Temperature side:
5 minutes = 22.0oC

Temperature inside:
5 minutes = 23.4oC

U-Value of loft insulation: 0.16W/m2K
Area of top: 30 x 60 = 120 cm2
Temperature difference: 1.4oC

Heat lost per second (W) = U-Value x area x temperature difference
= 0.16 x 120 x 1.4

(And I have worked this out one of the experiments - found the U value of aluminium online lol)

U-Value
The lower the U-value, the better an insulator the material is. It is measured in W/m2K and shows the amount of heat lost in watts (W) per square metre of material when the temperature (K) is one degree lower outside.

The term “U” value represents overall thermal conductance from the outside to the inside covering all modes of heat transfer. It can be defined as the heat flow over unit area of any building component through unit overall temperature difference between both sides of the component. The U-value is an important way of showing how well an element conducts heat from one side to another, which makes it the reciprocal of its thermal resistance. So, if the thermal resistance is worked out, it can be inverted to obtain the U-value.
U = 1 / Rt
U = 1/ (R so + ∑Rn + Rsi)

[COLOR="rgb(255, 140, 0)"]See how I'm confused [/COLOR]

[di marco]

that completely confused me just reading it lol! i was never any good at physics