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: When a [[force]] acts on an [[object]] with a [[pivot]] it becomes a turning force called a [[moment]].
: A '''moment''' can be calculated by multiplying a [[force]] by the [[distance]] from a [[pivot]].
: The [[unit]]s of a '''moment''' are [[Newton Metre]]s (Nm).
: '''Moments''' can be used to make [[Force Multiplier]]s using a [[pivot]] and [[lever]].
: The longer the lever, the larger the [[moment]] that can be produced.
{| class="wikitable"
|-
|[[File:PivotLever.png|center|400px]]
|-
| style="height:20px; width:200px; text-align:center;" |Using '''moments''' an effort can be used to lift a load. If the [[pivot]] is closer to the load than the effort then the [[force]] of effort can be smaller than the load to lift the [[object]].
|}
===Equation===
Moment = Force x Perpendicular distance from the pivot.
Where:
: M = [[Moment]]
===Example Calculations===
{| class="wikitable"
|-
| style="height:20px; width:200px; text-align:center;" |'''A 20N force of effort is applied at a [[perpendicular]] distance of 0.15m from the pivot. Calculate the Moment.'''
| style="height:20px; width:200px; text-align:center;" |'''A 20N force of effort is applied at a [[perpendicular]] distance of 14cm from the pivot. Calculate the Moment.'''
| style="height:20px; width:200px; text-align:center;" |'''A 20N force of effort is applied at a [[perpendicular]] distance of 100mm from the pivot. Calculate the Moment.'''
|-
|[[File:MomentSpanner1.png|center|200px]]
|[[File:MomentSpanner2.png|center|200px]]
|[[File:MomentSpanner3.png|center|200px]]
|-
| style="height:20px; width:200px; text-align:left;" |
Force = 20N
Perpendicular distance = 0.15m
<math>M = F \times d</math>
<math>M = 20 \times 0.15</math>
<math>M = 3.0Nm</math>
| style="height:20px; width:200px; text-align:left;" |
Force = 20N
Perpendicular distance = 14cm = 0.14m
<math>M = F \times d</math>
<math>M = 20 \times 0.14</math>
<math>M = 2.8Nm</math>
| style="height:20px; width:200px; text-align:left;" |
Force = 20N
Perpendicular distance = 100mm = 0.10m
<math>M = F \times d</math>
<math>M = 20 \times 0.10</math>
<math>M = 2.0Nm</math>
|}
===Extra Information===
{{#ev:youtube|https://www.youtube.com/watch?v=YlYEi0PgG1g}}
==Key Stage 4==
===Meaning===
A '''moment''' is the turning effect of a [[force]].
===About Moments===
: When a [[force]] acts on an [[object]] with a [[pivot]] it becomes a turning force called a [[moment]].
: A '''moment''' can be calculated by multiplying a [[force]] by the [[distance]] from a [[pivot]].
: The [[unit]]s of a '''moment''' are [[Newton Metre]]s (Nm).
: '''Moments''' can be used to make [[Force Multiplier]]s using a [[pivot]] and [[lever]].
: The longer the lever, the larger the [[moment]] that can be produced.
{| class="wikitable"
|-
|[[File:PivotLever.png|center|400px]]
|-
| style="height:20px; width:200px; text-align:center;" |Using '''moments''' an effort can be used to lift a load. If the [[pivot]] is closer to the load than the effort then the [[force]] of effort can be smaller than the load to lift the [[object]].
|}
===Equation===
Moment = Force x Perpendicular distance from the pivot.
<math>M = F \times d</math>
Where:
: M = [[Moment]]
: F = [[Force]]
: d = [[Perpendicular]] distance from the [[pivot]].
===Example Calculations===
{| class="wikitable"
| style="height:20px; width:200px; text-align:center;" |'''A hammer is used to pull out a nail from a wall. A 30N [[force]] of effort is applied at a [[perpendicular]] distance of 0.18m from the [[pivot]]. While the nail is 0.02m away from the pivot. Calculate the [[force]] applied to the nail at this point.'''
| style="height:20px; width:200px; text-align:center;" |'''A hammer is used to pull out a nail from a wall. A 30N [[force]] of effort is applied at a [[perpendicular]] distance of 19cm from the [[pivot]]. While the nail is 4cm away from the pivot. Calculate the [[force]] applied to the nail at this point.'''
| style="height:20px; width:200px; text-align:center;" |'''A hammer is used to pull out a nail from a wall. A 30N [[force]] of effort is applied at a [[perpendicular]] distance of 200mm from the [[pivot]]. While the nail is 60mm away from the pivot. Calculate the [[force]] applied to the nail at this point.'''
|-
|[[File:MomentHammer1.png|center|200px]]
|[[File:MomentHammer2.png|center|200px]]
|[[File:MomentHammer3.png|center|200px]]
|-
| style="height:20px; width:200px; text-align:center;" |'''A 30N force of effort is applied at a [[perpendicular]] distance of 0.18m from the pivot. Calculate the Moment.'''
| style="height:20px; width:200px; text-align:center;" |'''A 30N force of effort is applied at a [[perpendicular]] distance of 19cm from the pivot. Calculate the Moment.'''
| style="height:20px; width:200px; text-align:center;" |'''A 30N force of effort is applied at a [[perpendicular]] distance of 200mm from the pivot. Calculate the Moment.'''
|-
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 30N
Perpendicular distance between effort and pivot = 0.18m
Perpendicular distance between effort and pivot = 0.02m
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 30N
Perpendicular distance between effort and pivot = 19cm = 0.19m
Perpendicular distance between effort and pivot = 4cm = 0.04m
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 30N
Perpendicular distance between effort and pivot = 200mm = 0.200m
Perpendicular distance between effort and pivot = 60mm = 0.06m
|-
| style="height:20px; width:200px; text-align:left;" |'''2. Find the [[moment]] caused by the [[effort]].'''
<math>M = F \times d</math>
<math>M = 30 \times 0.18</math>
<math>M = 5.4Nm</math>
| style="height:20px; width:200px; text-align:left;" |'''2. Find the [[moment]] caused by the [[effort]].'''
<math>M = F \times d</math>
<math>M = 30 \times 0.19</math>
<math>M = 5.7Nm</math>
| style="height:20px; width:200px; text-align:left;" |'''2. Find the [[moment]] caused by the [[effort]].'''
<math>M = F \times d</math>
<math>M = 30 \times 0.20</math>
<math>M = 6.0Nm</math>
|-
| style="height:20px; width:200px; text-align:left;" |'''3. Calculate the Force applied to the nail from the [[moment]].'''
Moment = 5.4Nm
Perpendicular distance = 0.02m
<math>M = F \times d</math>
<math>5.4 = F \times 0.02</math>
<math>F = \frac{5.4}{0.02}</math>
<math>F = 270N</math>
| style="height:20px; width:200px; text-align:left;" |'''3. Calculate the Force applied to the nail from the [[moment]].'''
Moment = 5.7Nm
Perpendicular distance = 4cm = 0.04m
<math>M = F \times d</math>
<math>5.7 = F \times 0.04</math>
<math>F = \frac{5.7}{0.04}</math>
<math>F = 142.5N</math>
| style="height:20px; width:200px; text-align:left;" |'''3. Calculate the Force applied to the nail from the [[moment]].'''
Moment = 6.0Nm
Perpendicular distance = 60mm = 0.06m
<math>M = F \times d</math>
<math>6.0 = F \times 0.06</math>
<math>F = \frac{6.0}{0.06}</math>
<math>F = 100N</math>
|}
===References===
====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 ''Moment, pages 168-9, GCSE Physics; Student Book, Collins, 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=f0dfb66dafcb0c6e9449e7b1a4ae1ac317 ''Moments, page 57, 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 ''Moments, pages 120-123, 126-127, GCSE Physics; Third Edition, Oxford University Press, 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 ''Moments, pages 165, 166, GCSE Physics; The Complete 9-1 Course for AQA, 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 ''Moments, page 136, GCSE Physics, Pearson 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 ''Moments, page 68, GCSE Physics; 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 ''Moments, pages 211-213, GCSE Physics, CGP, Edexcel '']
====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 ''Moment (turning effect), pages 84-85, Gateway GCSE Physics, Oxford, 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 ''Moments, pages 38, 39, Gateway GCSE Physics; The Revision Guide, CGP, OCR  '']