How ==Key Stage 3=====Meaning===[[Speed]] is how fast something is moving, [[measure|measured]] in [[Metres per Second|metres per second]]. ===About Speed===: The scientific [[unit]]s of [[speed]] are [[Metres per Second]].: [[Speed]] is commonly measured in the [[unit]]s of [[Miles per Hour]], but this is not a scientific [[unit]].: Other [[unit]]s of [[speed]] can be given by the [[unit]]s of [[distance]] used and the [[unit]]s of [[time]] used in the calculation of [[speed]].: [[Speed]] can be found by [[measuring]] the [[distance]] travelled by an [[object]] in a given [[time]]. ===Equation===:<math>Speed = {\tfrac{distance}{time}} </math>:<math>s = {\tfrac{D}{t}} </math>Where:: s = Speed: D = Distance: t = Time ===Example Calculations==={| class="wikitable"|-| style="height:20px; width:300px; text-align:center;" |'''A person jogs 300 [[metre]]s in 120 [[second]]s. Calculate the speed of the jogger.'''| style="height:20px; width:300px; text-align:center;" |'''A racing car travels 500 [[metre]]s in 10 [[second]]s. Calculate the speed of the racing car.'''|-| style="height:20px; width:300px; text-align:left;" |distance = 300[[m]] time = 120[[s]] <math>Speed = {\tfrac{distance}{time}} </math> <math>Speed = {\tfrac{300}{120}} </math> <math>Speed = 2.5m/s </math>| style="height:20px; width:300px; text-align:left;" |distance = 500[[m]] time = 10[[s]] <math>Speed = {\tfrac{distance}{time}} </math> <math>Speed = {\tfrac{500}{10}} </math> <math>Speed = 50m/s </math>|-| style="height:20px; width:300px; text-align:center;" |'''A [[horse]] takes 20 [[minute]]s to trot 2.4 [[kilometre]]s. Calculate the speed of the [[horse]] in [[Metres per second|metres per second]].'''| style="height:20px; width:300px; text-align:center;" |'''The International Space Station takes 92 [[minute]]s to orbit the Earth once travelling 42,000 [[kilometre]]s. Calculate the speed of the ISS.'''|-| style="height:20px; width:300px; text-align:left;" |distance = 2.4[[km]] = 2400[[m]] time = 20[[min]] = 1200[[s]] <math>Speed = {\tfrac{distance}{time}} </math> <math>Speed = {\tfrac{2400}{1200}} </math> <math>Speed = 2m/s </math>| style="height:20px; width:300px; text-align:left;" |distance = 42,000[[km]] = 42,000,000[[m]] time = 20[[min]] = 5400[[s]] <math>Speed = {\tfrac{distance}{time}} </math> <math>Speed = {\tfrac{42000000}{5400}} </math> <math>Speed = 7608.7m/s </math> <math>Speed \approx 7600m/s </math>|}