IB›IB Physics HL›Mind mapsA.1 KinematicsIB Physics HL: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsDescribing motionDisplacement is a vector; distance is a scalarFull lap: distance 400 m, zero displacementVelocity = rate of change of positionAcceleration = rate of change of velocityGraphsGradient of tangent on s–t gives instantaneous velocityGradient of v–t gives accelerationArea under v–t gives displacementArea under a–t gives change in velocityUniform accelerationOnly valid when acceleration is constantv=u+atv = u + atv=u+ats=ut+12at2s = ut + \frac{1}{2}at^2s=ut+21at2v2=u2+2asv^2 = u^2 + 2asv2=u2+2ass=u+v2ts = \frac{u+v}{2}ts=2u+vtKinematicsdescribing motionsuvatProjectilesHorizontal: constant velocity, x=uxtx = u_x tx=uxtVertical: acceleration g downwardsComponents linked only by timeAt the top, only vertical velocity is zeroTime of flight on level ground =2uy/g= 2u_y/g=2uy/gFluid resistanceDrag opposes velocity, grows with speedRange and maximum height decreasePath is asymmetric, steeper on the way downTerminal speed when drag equals weightExam tipsGive every vector a signUneven velocity change in equal times means non-uniformChoose the equation with three knowns and one unknownSpeed at top of trajectory is not zero