IGCSE›Edexcel IGCSE Physics›Mind mapsMovement & PositionEdexcel IGCSE Physics: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsDistance-timeFlat line means stationaryStraight slope means constant speedCurve means speed is changingGradient gives the speedaverage speed=distancetime\text{average speed} = \frac{\text{distance}}{\text{time}}average speed=timedistanceAccelerationRate of change of velocitya=v−uta = \frac{v - u}{t}a=tv−uMeasured in m/s²Example: 0 to 20 m/s in 5 s gives 4 m/s²Velocity-timeGradient gives the accelerationFlat line means constant velocitySlopes up: speeding up; slopes down: deceleratingArea under line gives distance travelledMotion graphsspeed and accelerationmsm/sm/s²No time givenUse v2=u2+2asv^2 = u^2 + 2asv2=u2+2asHandy for stopping distance and brakingu=10u = 10u=10, a=2a = 2a=2, s=24s = 24s=24 gives v=14 m/sv = \mathbf{14}\,\text{m/s}v=14m/sPracticalMeasure distance at regular time intervalsLight gates cut reaction-time errorRepeat and average for reliabilityExam tipsDescribe specific sections, e.g. 0 to 5 sState stationary, constant speed or acceleratingSplit odd shapes into triangles and rectanglesMention reaction time when evaluating a method