Kinematics of Linear Motion, Glossary

Knowing the vocabulary of Kinematics of Linear Motion precisely is worth easy marks in SPM Add Math. Questions often turn on a single keyword, read it correctly and the method follows; misread it and even good algebra earns nothing.

Because the SPM paper is bilingual (BM/EN), each term below shows the English and Malay wording, so your child recognises it whichever way a question is phrased.

• Displacement, Displacement is the position of a moving particle relative to a fixed point, measured along a straight line, and it can be positive, negative, or zero. As a vector quantity it has direction, so it differs from distance. It is often written as a function of time, $s=f(t)$. →
• Velocity, Velocity is the rate of change of displacement with respect to time, found by differentiating: $v=\frac{ds}{dt}$. As a vector it has direction, so a negative velocity means motion in the opposite direction. When velocity is zero, the particle is momentarily at rest. →
• Acceleration, Acceleration is the rate of change of velocity with respect to time, found by differentiating velocity: $a=\frac{dv}{dt}=\frac{d^{2}s}{dt^{2}}$. It shows how quickly the particle is speeding up or slowing down. A negative acceleration while moving forward means the particle is decelerating. →
• Instantaneous Velocity, Instantaneous velocity is the velocity of a particle at one exact moment, rather than an average over an interval. It is obtained by differentiating the displacement function and substituting the given time, $v=\frac{ds}{dt}$. Initial velocity is its value at $t=0$. →
• Instantaneous Acceleration, Instantaneous acceleration is the acceleration of a particle at a specific instant, found by differentiating the velocity function and substituting the given time, $a=\frac{dv}{dt}$. At maximum or minimum velocity the acceleration is zero, which helps locate those turning points in the motion. →
• Total Distance Travelled, The total distance travelled is the whole length of the path a particle covers, counting motion in both directions as positive. It differs from displacement, which can be smaller because opposite movements cancel. If the particle changes direction, the journey must be split at the moment velocity is zero. →

Do not just memorise definitions, practise using each term inside a full solution, the way a marker expects to see it. In the Kinematics of Linear Motion chapter especially, stating the right definition or condition in your working can itself earn a method mark.

Our teachers check that a student can both recall a term and deploy it fluently under exam conditions.

Vocabulary sticks best when it is tied to doing rather than reading. Instead of learning the Kinematics of Linear Motion terms as a flat list, meet each one inside a worked question and say the step aloud in words as you write it, a term you can use in a sentence is a term you understand.

It also helps to link related terms together rather than in isolation, since Kinematics of Linear Motion questions usually combine several ideas at once. Because the SPM paper is bilingual, glance once at the Malay and English wording of each term side by side, so the language a question is set in never throws you.

If a term keeps feeling slippery, that is usually a sign the underlying idea needs another look, not the word itself, and that is exactly the kind of gap a one-to-one lesson closes quickly.