IGCSE›Cambridge IGCSE Physics›Mind mapsPhysical Quantities and Measurement TechniquesCambridge IGCSE Physics: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsLength and volumeRuler for length, eye level to avoid parallaxMeasuring cylinder for volume of liquidsRead the bottom of the meniscusSolid volume by displacement methodTimingDigital timers are more precise than stopwatchesHuman reaction time is about ±0.2 sTime many oscillations, then divide20 swings in 25 s → period 1.25 sScalarsMagnitude onlyDistance, speed, time, massEnergy and temperature tooMeasurementquantities and techniquesR=a2+b2R = \sqrt{a^2 + b^2}R=a2+b2VectorsMagnitude and directionForce, weight, velocity, accelerationMomentum and field strengthsResultantsRight angles: R=a2+b2R = \sqrt{a^2 + b^2}R=a2+b23 N and 4 N give 5 NOr use a scale drawing and protractorExam tipsRepeat readings and take the meanAveraging reduces random errorSay eye level with the scaleAsk: does it need a direction?