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Mass
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: '''Mass''' is measured in [[Gram|grams]] and [[Kilogram|kilograms]].
==Note to Teachers==
Students are frequently confused by the difference between mass and weight. This is in part due to the terms being used interchangeably during KS1 maths. It is also due to grams and kilograms being falsely referred to as weight in common parlance. The conceptual difference that mass is 'the amount of stuff in an object' and weight is 'the amount of force pulling an object down' should not be too complicated for a student. However, breaking the habit of using the words interchangeably proves challenging. Teachers should do their best to say 'mass' whenever they are talking about grams or kilograms and say Newtons, stone, pounds or ounces when talking about weight. A useful rule is to remember than on Earth 1kg weighs 10 Newtons. This gives an easy conversion when you want to talk about weight instead of mass. This is different in space where; on the moon 1kg weighs 1.6 Newtons and on Jupiter 1kg weighs 25 Newtons.
==Key Stage 3==
===Meaning===
[[Mass]] is the amount of [[matter]] that something is made of, [[Measure|measured]] in [[Kilogram|kilograms]].
===About Mass===
: '''Mass''' can be measured using a [[Measuring Scale|measuring scale]].
: The more [[mass]] an [[object]] has, the harder it is to [[accelerate]] the [[object]].
The [[unit]]s of [[mass]] you should be able to use are:
*[[Kilogram]]s: For [[object]]s that can be lifted by [[human]]s.
*[[Gram]]s: For quantities of [[chemical]]s used in a [[Chemical Reaction|chemical reactions]].
==Key Stage 4 Foundation==
===Meaning===
[[Mass]] is the amount of [[matter]] that something is made of, [[Measure|measured]] in [[Kilogram|kilograms]].
===About Mass===
: '''Mass''' can be measured using a [[Measuring Scale|measuring scale]] or [[Electronic Balance]].
: The [[SI Unit]] of [[mass]] is the [[kilogram]].
: [[Mass]] is a [[scalar]] quantity as it has [[magnitude]] but does not have a direction.
: The more [[mass]] an [[object]] has, the harder it is to [[accelerate]] the [[object]].
The [[unit]]s of [[mass]] you should be able to use are:
*[[Megagram]]s: Also known as [[ton]]s. There are 1000kg in one [[megagram]].
*[[Kilogram]]s: For [[object]]s that can be lifted by [[human]]s.
*[[Gram]]s: For quantities of [[chemical]]s used in a [[Chemical Reaction|chemical reactions]]. There are 1000g in 1 [[kilogram]].
*[[Milligram]]s: For doses of [[medicine]]. There are 1000,000mg in a [[kilogram]].
*[[Microgram]]s: For [[Vitamin]]s and other [[micronutrient]]s. There are 1000,000,000µg in a [[kilogram]].
==Key Stage 4 Higher==
===Meaning===
'''Inertial mass''' is <math>mass = \frac{Force}{acceleration}</math>; the [[ratio]] of [[force]] to the [[acceleration]] of an [[object]].
===About Inertial Mass===
: '''Mass''' is the resistance of an [[object]] to being [[accelerated]]. The greater the [[mass]] the more [[force]] is needed to [[accelerate]] it.
: '''Mass''' can be measured using a [[Measuring Scale|measuring scale]] or [[Electronic Balance]].
: The [[SI Unit]] of [[mass]] is the [[kilogram]].
: [[Mass]] is a [[scalar]] quantity as it has [[magnitude]] but does not have a direction.
The [[unit]]s of [[mass]] you should be able to use are:
*[[Megagram]]s: Also known as tons. There are 1000kg in one [[megagram]].
*[[Kilogram]]s: For [[object]]s that can be lifted by [[human]]s.
*[[Gram]]s: For quantities of [[chemical]]s used in a [[Chemical Reaction|chemical reactions]]. There are 1000g in 1 [[kilogram]].
*[[Milligram]]s: For doses of [[medicine]]. There are 1000,000mg in a [[kilogram]].
*[[Microgram]]s: For [[Vitamin]]s and other micronutrients. There are 1000,000,000µg in a [[kilogram]].
*[[Nanogram]]s: The [[mass]] of [[Cell (Biology)|cells]] in [[organism]]s. There are 1000,000,000,000ng in a [[kilogram]].
===Equation===
''NB: You need to remember this equation.''
Inertial Mass = (Resultant Force)/(Acceleration)
<math>m = \frac{Force}{acceleration}</math>
Where
<math>m</math> = The '''Inertial Mass''' of the [[object]].
<math>F</math> = The [[Resultant Force]] on the [[object]].
<math>a</math> = The [[acceleration]] of the [[object]].
===Example Calculations===
====Finding the Inertial Mass given the Force and Acceleration====
{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |An [[object]] is subjected to a [[Resultant Force|resultant force]] of 92N and [[accelerate]]s at a rate of 0.42m/s/s. Calculate the '''inertial mass''' of the [[object]] correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:300px; text-align:center;" |The brakes of a car provide a [[force]] of 12kN and are able to [[decelerate]] it at a rate of 8.7m/s/s. Calculate the '''intertial mass''' of the car correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
a = 0.42m/s/s
F = 92N
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
a = 8.7m/s/s
F = 12kN = 12 x 10<sup>3</sup>N
|-
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math>m= \frac{F}{a}</math>
<math>m = \frac{92}{0.42}</math>
<math>m = 219.047619kg</math>
<math>m \approx 220kg</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math>m= \frac{F}{a}</math>
<math>m = \frac{12 \times 10^3}{8.7}</math>
<math>m = 1379.31034kg</math>
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=Note to TeachersUTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Inertial mass, page 165, GCSE Combined Science Trilogy; Physics, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Inertial mass, page 197, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']: Students are frequently confused by the difference between [https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac251 ''Inertial mass and weight, page 65, GCSE Physics; The Revision Guide, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac298 ''Mass, page 52, GCSE Physics; The Revision Guide, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Mass, pages 11-13, 76-78, 124-125, 145-146, 150-153, GCSE Physics; Third Edition, Oxford University Press, AQA '']:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Mass, pages 129, 130, GCSE Combined Science Trilogy; Physics, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Mass, pages 149, 150, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']:[https://www.amazon.co. This is in part due to the terms being used interchangeably during KS1 mathsuk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Mass, pages 152-3, GCSE Physics; Student Book, Collins, AQA '']:[https://www.amazon. It is also due to grams and kilograms being falsely referred to as weight in common parlanceco. uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10058 ''Mass, pages 195, 204, 212, GCSE Combined Science; The conceptual difference that Revision Guide, CGP, AQA ''] ====Edexcel==== :[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 ''Inertial mass, page 19, GCSE Physics, Pearson Edexcel '']:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Inertial mass is , page 303, GCSE Combined Science, Pearson Edexcel '']:[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Mass, page 150, GCSE Combined Science; The Revision Guide, CGP, 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 ''Mass, page 37, GCSE Physics, CGP, Edexcel '']:[https://www.amazon.co.uk/gp/product/1782945733/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945733&linkCode=as2&tag=nrjc-21&linkId=2a2dbec9db6bf5766c0458d908fa0a52 ''Mass, page e17, GCSE Physics; The Revision Guide, CGP, Edexcel '']:[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 ''Mass, pages 16-17, GCSE Physics, Pearson Edexcel '']:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Mass, pages 216, 300-301, GCSE Combined Science, 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 ''the amount Mass; conservation in changes of stuff in an objectstate, page 303, GCSE Physics, CGP, Edexcel '']:[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 ''Mass; conservation of, page 182, GCSE Physics, Pearson Edexcel '']:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ' and weight is 'the amount Mass; conservation of force pulling an object down, pages 218-219, 414, GCSE Combined Science, Pearson Edexcel '']:[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 ''Mass; inertial, page 19, GCSE Physics, Pearson Edexcel '']:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Mass; inertial, page 303, GCSE Combined Science, 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 ''Mass; inertial, page 36, GCSE Physics, CGP, 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 ' is should not be too complicated for a student'Mass; measuring, page 33, GCSE Physics, CGP, Edexcel '']:[https://www.amazon.co. Howeveruk/gp/product/1292120215/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120215&linkCode=as2&tag=nrjc-21&linkId=8f96ddb76196848bafdb124354e4cf77 ''Masses, page 72, GCSE Chemistry, Pearson, breaking the habit Edexcel ''] ====OCR====:[https://www.amazon.co.uk/gp/product/1782945679/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945679&linkCode=as2&tag=nrjc-21&linkId=a2db42f7b4bdf10cafaafa3bb9120940 ''Mass (units of using the words interchangeably proves challenging), page 9, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR '']:[https://www. Teachers should do their best to say 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 'mass' whenever they are talking about grams or kilograms and say NewtonsMass, pages 13, 14, 33, Gateway GCSE Physics; The Revision Guide, stoneCGP, pounds or ounces when talking about weightOCR '']:[https://www. A useful rule is to remember than on Earth 1kg weighs 10 Newtonsamazon. This gives an easy conversion when you want to talk about weight instead of massco. This is different in space whereuk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Mass, pages 151, 166, Gateway GCSE Combined Science; on the moon 1kg weighs 1The 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 ''Mass, pages 24, 250, Gateway GCSE Physics, Oxford, OCR '']:[https://www.amazon.6 Newtons and on Jupiter 1kg weighs 25 Newtonsco.uk/gp/product/0198359829/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359829&linkCode=as2&tag=nrjc-21&linkId=90e8d7b4f039d53035238fa0320fe00b ''Mass, pages 90-91, 97-99, 164, Gateway GCSE Chemistry, Oxford, OCR '']