![\"IB](\"https:\/\/times.edu.vn\/wp-content\/uploads\/2026\/09\/IB-Physics-key-terms.webp\")
<\/p>\nIB Physics key terms are the precise scientific words and definitions students need to communicate physical ideas clearly and meet mark scheme expectations. Essential vocabulary spans mechanics, fields, waves, electricity and magnetism, and nuclear and quantum physics, with many definitions requiring specific scientific wording rather than everyday language. Using accurate terminology is especially important in Define, Describe, and Explain questions, where imprecise phrasing can cost marks even when the underlying concept is understood.<\/p>\n
This guide explains the most important IB Physics key terms, their meanings, and how students can learn and apply them effectively in exams.<\/p>\n
<\/p>\n
Mechanics forms the backbone of the IB Physics<\/a> [1]<\/a><\/sup> curriculum under Theme A: Space, Time, and Motion. A common mistake we see at Times Edu<\/a> is students using everyday language when scientific definitions are required, and this costs marks on Paper 2 consistently.<\/p>\n Below are the most critical mechanics terms IB<\/a> Physics students must be able to define with precision:<\/p>\n One critical detail often overlooked is the scalar versus vector distinction. The IB mark scheme will not award a definition mark for “velocity” if you describe it simply as “how fast something moves.” You must state both the rate of change of displacement and the vector nature of the quantity.<\/p><\/blockquote>\n Mass vs weight<\/strong> is another classic trap in this theme. Mass is the measure of the amount of matter in an object, measured in kilograms. Weight is the gravitational force acting on that mass, measured in Newtons. In IB Physics, mass and weight are never interchangeable, and using them incorrectly in an explanation will cost you the definition mark every time.<\/p>\n\n\t\n
\n Term<\/th>\n Precise IB definition<\/th>\n Common student error<\/th>\n<\/tr>\n \n Displacement<\/td>\n Linear distance and direction from a fixed reference point (vector)<\/td>\n Writing “distance” instead of “distance and direction”<\/td>\n<\/tr>\n \n Velocity<\/td>\n Rate of change of displacement with respect to time (vector)<\/td>\n Confusing with speed, which is scalar<\/td>\n<\/tr>\n \n Acceleration<\/td>\n Rate of change of velocity with respect to time (vector)<\/td>\n Saying “change in speed” rather than “change in velocity”<\/td>\n<\/tr>\n \n Terminal speed<\/td>\n Constant speed reached when gravitational force exactly balances drag force<\/td>\n Failing to state that net force equals zero<\/td>\n<\/tr>\n \n Impulse<\/td>\n Product of net force and the time interval of its action, equal to change in momentum<\/td>\n Omitting the phrase “net force” or “change in momentum”<\/td>\n<\/tr>\n<\/table>\n