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: Objects have [[weight]] because of the [[gravity]] of the [[Earth]].
: [[Weight]] can be [[Measure|measured]] using a [[Newton Meter]] or a [[Measuring Scale]].
: [[Weight]] is [[Measure|measured]] in [[Newton (Unit)|Newtons]] s but can also be [[Measure|measured]] in [[Stone (Unit)|stone]], [[Pound (Unit)|pounds]] and [[Ounce (Unit)|ounces]].
: [[Weight]] depends on the amount of [[mass]] an [[object]] has.
{| class="wikitable"
|-
|[[File:WeightTennisBall.png|center|100px75px]]|[[File:WeightBowlingBall.png|center|200px150px]]|[[File:WeightBoat.png|center|250px190px]]
|-
| style="height:20px; width:200px; text-align:center;" |[[Weight]] makes a tennis ball fall to the ground.
| style="height:20px; width:200px; text-align:center;" |If the [[weight]] of a boat were bigger than the [[upthrust]] the boat would sink.
|-
|[[File:WeightCar.png|center|250px190px]]|[[File:WeightSubmarine.png|center|250px190px]]|[[File:WeightPlane.png|center|250px190px]]
|-
| style="height:20px; width:200px; text-align:center;" |The [[weight]] of the [[car]] acts from its [[Centre of Mass|centre of mass]].
===Equation===
: Weight = Mass x Gravitational Field Strength
Where:
: W = Weight
: The [[weight]] of an [[object]] is due to [[gravity]].
The [[magnitude]] of the [[weight]] depends on:
:*The [[mass]] of the [[object]] - The more [[mass]]ive the [[object]] the greater the [[force]] of [[weight]].:*The [[Gravitational Field Strength|gravitational field strength]] - The greater the [[Gravitational Field Strength|gravitational field strength]] the greater the [[force]] of [[weight]].
: [[Weight]] always acts towards the centre of [[mass]] of a [[moon]], [[planet]] or [[star]].
: The [[weight]] of an [[object]] acts from its [[Centre of Mass|centre of mass]] (or [[Centre of Gravity|centre of gravity]])of an [[object]].: On [[Earth]] the [[Gravitational Field Strength|gravitational field strength]] is 9.8[[N/kg]] correct to two [[Significant Figures|significant figures]]. ===Examples==={| class="wikitable"|-|[[File:WeightTennisBall.png|center|75px]]|[[File:WeightBowlingBall.png|center|150px]]|[[File:WeightBoat.png|center|190px]]|-| style="height:20px; width:200px; text-align:center;" |[[Weight]] makes a tennis ball fall to the ground.| style="height:20px; width:200px; text-align:center;" |[[Weight]] holds the bowling ball to the ground.| style="height:20px; width:200px; text-align:center;" |If the [[weight]] of a boat were bigger than the [[upthrust]] the boat would sink.|-|[[File:WeightCar.png|center|190px]]|[[File:WeightSubmarine.png|center|190px]]|[[File:WeightPlane.png|center|190px]]|-| style="height:20px; width:200px; text-align:center;" |The [[weight]] of the [[car]] acts from its [[Centre of Mass|centre of mass]].| style="height:20px; width:200px; text-align:center;" |The submarine has the same [[weight]] under the water as it would on land, but in the water this is [[Balanced Forces|balanced]] by the [[upthrust]].| style="height:20px; width:200px; text-align:center;" |Planes can be very heavy but their [[weight]] is [[Balanced Forces|balanced]] by the [[lift]].|} ===Equation=== Weight = Mass x Gravitational Field Strength <math>W = m \times g </math> Where <math>W</math> = The [[weight]] of the [[object]]. <math>W = m \times g </math> = The [[mass]] of the [[object]]. <math>W = m \times g </math> = The [[Gravitational Field Strength|gravitational field strength]] of the [[Gravitational Field|gravitational field]] the [[object]] is in. ===Calculating Weight from Mass and Gravitational Field Strength==={| class="wikitable"|-| style="height:20px; width:200px; text-align:center;" |'''Calculate the [[weight]] of a 25[[kg]] object on [[Earth]] correct to two [[Significant Figure|significant figures]]'''| style="height:20px; width:200px; text-align:center;" |'''A 550[[kg]] space probe is sent into deep space beyond the gravitational field of any other [[object]]. Calculate the weight of the space probe correct to two [[Significant Figures|significant figures]].'''| style="height:20px; width:200px; text-align:center;" |'''[[The Moon]] has a [[Gravitational Field Strength|gravitational field strength]] of 1.6[[N/kg]]. Calculate the weight of a 85[[kg]] astronaut on [[The Moon]] correct to two [[Significant Figures|significant figures]].'''|-| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s.'''m = 25[[kg]] g<sub>Earth</sub> = 9.8[[N/kg]]| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s.'''m = 550[[kg]] g<sub>Deep Space</sub> = 0[[N/kg]]| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities in [[SI Unit]]s.'''m = 550[[kg]]m = 85[[kg]] g<sub>The Moon</sub> = 1.6[[N/kg]]|-| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''<math>W = m \times g </math> <math>W = 25 \times 9.8 </math> <math>W = 245N </math> <math>W \approx 250N </math>| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''<math>W = m \times g </math> <math>W = 550 \times 0 </math> <math>W = 0.0N </math>| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''<math>W = m \times g </math> <math>W = 85 \times 1.6 </math> <math>W = 136N </math> <math>W \approx 140N </math>|} ===References=======AQA==== :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Weight, page 120, GCSE Physics, Hodder, AQA '']:[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10437 ''Weight, page 204, GCSE Combined Science; 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=f0dfb66dafcb0c6e9449e7b1a4ae1ac510 ''Weight, page 52, GCSE Physics; The Revision Guide, CGP, 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 ''Weight, 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 ''Weight, pages 149, 150, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Weight, pages 152-3, GCSE Physics; Student Book, Collins, AQA '']:[https://www.amazon.co.uk/gp/product/1471851362/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851362&linkCode=as2&tag=nrjc-21&linkId=7d78d70a2044ee9982dae010c94af92a ''Weight, pages 210, GCSE Combined Science Trilogy 2, Hodder, 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 ''Weight, pages 4-5, 10-11, 146-147, GCSE Physics; Third Edition, Oxford University Press, AQA ''] ====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 ''Weight, page 150, GCSE Combined Science; The Revision Guide, 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 ''Weight, pages 17, 102, 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 ''Weight, pages 2, 16-17, 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 ''Weight, pages 37, 38, 333, 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 ''Weight, page 166, 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 ''Weight, page 33, 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 ''Weight, pages 63, 82, Gateway GCSE Physics, Oxford, OCR '']