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===About Pressure===
: [[Pressure]] is [[measure]]d in [[Pascal]]s ([[Pa]]).
: A large [[force]] on a small [[area]] causes a large [[pressure]].
: A small [[force]] on a large [[area]] causes a small [[pressure]].
===Equation===
: [[Pressure]] = [[(Force]])/[[(Area]])
:<math>P = \frac{F}{A}</math>
Where:
: P = [[Pressure]]: F = [[Force]]: A = [[Area]]
===Example Calculations===
| style="height:20px; width:200px; text-align:center;" |'''A hydraulic press is used to stamp metal. The press provides a force of 1000N over an area of 0.0002m<sup>2</sup>. Calculate the Pressure applied by the press.'''
| style="height:20px; width:200px; text-align:center;" |'''A 25000[[N]] elephant stands on 4 feet. The area of each foot is 0.01m<sup>2</sup>. Calculate the pressure on one foot.'''
| style="height:20px; width:200px; text-align:center;" |'''A person wearing stilettos rests their entire weight of 600N on one heel. The heel has an area of 0.0005m<sup>2</sup>. Calculate the [[pressure]] due to the heel of the stiletto.'''
|-
| style="height:20px; width:200px; text-align:left;" |
A = 0.0002m<sup>2</sup>
:<math>P = \tfracfrac{F}{A}</math>
:<math>P = \tfracfrac{1000}{0.0002}</math>
:<math>P = 5,000,000Pa</math>
Area of 4 feet = 0.04m<sup>2</sup>
:<math>P = \tfracfrac{F}{A}</math>
:<math>P = \tfracfrac{25000}{0.04}</math>
:<math>P = 625,000Pa</math>
A = 0.0005m<sup>2</sup>
:<math>P = \tfracfrac{F}{A}</math>
:<math>P = \tfracfrac{600}{0.0005}</math>
:<math>P = 1,200,000Pa</math>
|}
===Pressure in a Fluid===
: The [[force]] responsible for [[pressure]] in a [[fluid]] is the [[weight]] of all the [[particle]]s above the [[object]].
: The [[pressure]] in a [[fluid]] decreases with height and increases with depth. The deeper into a [[fluid]] the greater the pressure.
: Since [[pressure]] increases with depth then the bottom of an [[object]] will experience more [[pressure]] than the top of the [[object]]. This causes a [[force]] called [[upthrust]].
==Key Stage 4==
===Meaning===
[[Pressure]] is the perpendicular [[force]] on a surface per unit [[area]].
===About Pressure===
: [[Pressure]] is [[measure]]d in [[Pascal]]s (Pa).
: A large [[force]] on a small [[area]] causes a large [[pressure]].
: A small [[force]] on a large [[area]] causes a small [[pressure]].
===Equation===
: [[Pressure]] = (Force)/(Area)
:<math>P = \frac{F}{A}</math>
Where:
: P = [[Pressure]]
: F = [[Force]]
: A = [[Area]]
===Example Calculations===
{| class="wikitable"
|-
| style="height:20px; width:200px; text-align:center;" |'''A hydraulic press is used to stamp metal. The press provides a force of 1100N over an area of 0.00023m<sup>2</sup>. Calculate the Pressure applied by the press correct to two [[Significant Figures|significant figures]].'''
| style="height:20px; width:200px; text-align:center;" |'''A 25000[[N]] elephant stands on 4 feet. The area of each foot is 0.012m<sup>2</sup>. Calculate the pressure on one foot correct to two [[Significant Figures|significant figures]].'''
| style="height:20px; width:200px; text-align:center;" |'''A person wearing stilettos rests their entire weight of 630N on one heel. The heel has an area of 0.00029m<sup>2</sup>. Calculate the [[pressure]] due to the heel of the stiletto correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 1100N
Area = 0.00023m<sup>2</sup>
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 25000N/4 = 6250N per foot.
Area = 0.012m<sup>2</sup>
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
Force = 630N
Area = 0.00029m<sup>2</sup>
|-
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
:<math>P = \frac{F}{A}</math>
:<math>P = \frac{1100}{0.00023}</math>
:<math>P = 4782608.696Pa</math>
:<math>P \approx 4800000Pa</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
:<math>P = \frac{F}{A}</math>
:<math>P = \frac{6250}{0.012}</math>
:<math>P = 520833.3Pa</math>
:<math>P \approx 520000Pa</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
:<math>P = \frac{F}{A}</math>
:<math>P = \frac{630}{0.00029}</math>
:<math>P = 2172413.793Pa</math>
:<math>P \approx 2200000Pa</math>
|}