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→Finding Density from Mass and Volume
: If an [[object]] is less '''dense''' than [[water]] it will rise through [[water]] and float on the surface.
===EquationFormula===
: Density = Mass/volume
:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Density; fluids, page 203, GCSE Physics, Pearson Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Density; states of matter, page 300, GCSE Physics, CGP, Edexcel '']
====OCR====
:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Density, page 151, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']
:[https://www.amazon.co.uk/gp/product/1782945687/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945687&linkCode=as2&tag=nrjc-21&linkId=9a598e52189317a20311d7a632747bc9 ''Density, pages 13, 14, Gateway GCSE Physics; The Revision Guide, CGP, OCR '']
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Density; Calculation, pages 24-25, Gateway GCSE Physics, Oxford, OCR '']
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Density; Measurement, pages 250-251, Gateway GCSE Physics, Oxford, OCR '']
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Density; Particle theory, pages 25, Gateway GCSE Physics, Oxford, OCR '']
==Key Stage 5==
===Meaning===
[[Density]] of a substance is its [[mass]] per [[unit]] volume.
===About Density===
*The [[unit]]s of [[density]] are typically [[kilogram]]s per cubic metre (kg/m³) or grams per cubic centimeter (g/cm³).
*[[Density]] is a fundamental property of [[material]]s and affects buoyancy, stability, and structural integrity.
*The [[density]] of a substance can change with [[temperature]] and [[pressure]].
*'''Density''' is used in calculating the [[mass]] of an [[object]] given its [[Volume (Space)|volume]], and vice versa.
*For an [[alloy]] the '''density''' of that [[alloy]] is found by [[sum]]ing the [[mass]] of each [[alloy]] divided by the total [[Volume (Space)|volume]]. However, where the [[Volume (Space)|volume]] of each component is known, not the [[mass]] then the [[mass]] is replaced with the [[Product (Maths)|product]] of the [[density]] and [[Volume (Space)|volume]] of each [[alloy]].
===Formula===
====Density of a single material====
'''Density''' of a [[material]] is given by the formula:
*<math>\rho = \frac{m}{V}</math>
Where:
ρ = The [[density]] of the [[object]].
m = The [[mass]] of the [[object]].
V = The [[Volume (Space)|volume]] taken up by the [[object]].
====Density of a composite or alloy material====
*<math>\rho = \frac{\rho_1V_1+\rho_2V_2}{V}</math>
*<math>\rho = \frac{\rho_1V_1}{V}+\frac{\rho_2V_2}{V}</math>
*<math>\rho = \frac{\rho_1V_1+\rho_2V_2}{V_1+V_2}</math>
ρ = The [[density]] of the [[alloy]]
ρ<sub>1</sub> = The [[density]] of one of the [[alloy]] composites
ρ<sub>2</sub> = The [[density]] of the other [[alloy]] composite
V<sub>1</sub> = The [[Volume (Space)|volume]] of one of the [[alloy]] composites
V<sub>2</sub> = The [[Volume (Space)|volume]] of the other [[alloy]] composite
V = The total [[Volume (Space)|volume]] taken up by the [[alloy]]
===Example Calculations===
====Finding Density of an Alloy given the density and volume of its composites====
{| class="wikitable"
|-
| style="height:20px; width:300px; text-align:center;" |'''A [[Volume (Space)|volume]] of 6.35x10<sup>-3</sup>m<sup>3</sup> [[Aluminium]] and 4.10x10<sup>-3</sup>m<sup>3</sup> [[Magnesium]] are [[alloy]]ed together. Given the density of [[Aluminium]] is 2700kgm<sup>-3</sup> and the density of [[Magnesium]] is 1700kgm<sup>-3</sup> then calculate the density of the [[alloy]]'''.
| style="height:20px; width:300px; text-align:center;" |'''A [[Volume (Space)|volume]] of 4.9x10<sup>-3</sup>m<sup>3</sup> [[Copper]] and 1.1x10<sup>-3</sup>m<sup>3</sup> [[Zinc]] are [[alloy]]ed together. Given the density of [[Copper]] is 8900kgm<sup>-3</sup> and the density of [[Zinc]] is 7100kgm<sup>-3</sup> then calculate the density of the [[alloy]]'''.
|-
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s'''
[[Aluminium]] [[Volume (Space)|volume]] = 6.35x10<sup>-3</sup>m<sup>3</sup>
[[Aluminium]] [[Density]] = 2700kgm<sup>-3</sup>
[[Magnesium]] [[Volume (Space)|volume]] = 4.10x10<sup>-3</sup>m<sup>3</sup>
[[Magnesium]] [[Density]] = 1700kgm<sup>-3</sup>
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s'''
[[Copper]] [[Volume (Space)|volume]] = 4.9x10<sup>-3</sup>m<sup>3</sup>
[[Copper]] [[Density]] = 8900kgm<sup>-3</sup>
[[Zinc]] [[Volume (Space)|volume]] = 1.1x10<sup>-3</sup>m<sup>3</sup>
[[Zinc]] [[Density]] = 7100kgm<sup>-3</sup>
|-
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
*<math>\rho = \frac{\rho_{Al}V_{Al}+\rho_{Mg}V_{Mg}}{V_{Al}+V_{Mg}}</math>
*<math>\rho = \frac{2700\times 6.35 \times 10^{-3} + 1700\times 4.10 \times 10^{-3}}{6.35 \times 10^{-3} + 4.10 \times 10^{-3}}</math>
*<math>\rho = 2310kgm^{-3}</math>
However, this assumes that the total [[Volume (Space)|volume]] of the [[object]] is simply the [[sum]] of the two [[Volume (Space)|volumes]] which is not necessarily the case due to the way different sized [[particle]]s form a [[lattice]].
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
*<math>\rho = \frac{\rho_{Cu}V_{Cu}+\rho_{Zn}V_{Zn}}{V_{Cu}+V_{Zn}}</math>
*<math>\rho = \frac{8900\times 4.9 \times 10^{-3} + 7100\times 1.1 \times 10^{-3}}{4.9 \times 10^{-3} + 1.1 \times 10^{-3}}</math>
*<math>\rho = 8600kgm^{-3}</math>
However, this assumes that the total [[Volume (Space)|volume]] of the [[object]] is simply the [[sum]] of the two [[Volume (Space)|volumes]] which is not necessarily the case due to the way different sized [[particle]]s form a [[lattice]].
|}