A.1 Kinematics
A.1.1 Scalars and vectors
A.1.2 Distance and displacement
A.1.3 Speed and velocity
A.1.4 Acceleration
A.1.5 Motion graphs
A.1.6 Equations of motion
A.1.7 Projectile motion
A.1.8 Relative motion
A.1.9 IB-style kinematics questions
A.1 Kinematics — Pre-Quiz Revision
Before starting the quiz, review the key ideas of motion: quantities, vectors,
graphs, constant acceleration, free fall and projectile motion. This page is designed
to help you revise quickly and visually.
1. Learning Roadmap
Quantities and Units
Every physical quantity needs a number and a unit. In kinematics, you will mainly use
metre, second, metre per second and metre per second squared.
Scalars and Vectors
Scalars have magnitude only. Vectors have magnitude and direction.
Direction is the key difference.
Distance and Displacement
Distance is the total path length. Displacement is the straight-line change from start
to finish.
Speed and Velocity
Average speed uses distance. Average velocity uses displacement.
2. Graph Interpretation Guide
Displacement–Time Graph
The gradient of a displacement-time graph gives velocity.
displacement
gradient = velocity
Velocity–Time Graph
The gradient gives acceleration. The area under the graph gives displacement.
velocity
area = displacement
3. Key Equations
Uniform Acceleration
Use these equations only when acceleration is constant.
Projectile Motion
Horizontal and vertical motion are treated separately. Time connects both components.
4. Common Mistakes
Velocity at the top is zero, but acceleration is not zero
In vertical motion, at the highest point the object has zero vertical velocity,
but acceleration is still downward due to gravity.
Distance and displacement are not the same
Distance is the total path length. Displacement depends only on the start and final positions.
Area under a velocity-time graph is displacement
Students often confuse gradient and area. For velocity-time graphs, area gives displacement.
SUVAT equations require constant acceleration
Do not use constant acceleration equations if the acceleration changes during the motion.
5. Quick Revision Cards
A.1.1 Physical quantities, units and dimensions
A physical quantity must include a magnitude and a unit. In kinematics, the most common
units are m, s, m s⁻¹ and m s⁻².
A.1.2 Scalars and vectors
Scalars have magnitude only. Vectors have magnitude and direction. Speed is scalar;
velocity is vector.
A.1.3 Distance and displacement
Distance is the total path travelled. Displacement is the straight-line change in position.
If an object returns to its start point, displacement is zero.
A.1.4 Speed and velocity
Average speed = distance/time. Average velocity = displacement/time.
A.1.5 Acceleration
Acceleration is the rate of change of velocity. If velocity and acceleration are opposite,
the object slows down.
A.1.6 Motion graphs
Displacement-time gradient gives velocity. Velocity-time gradient gives acceleration.
Velocity-time area gives displacement.
A.1.7 Uniform acceleration equations
Use v = u + at, s = ut + ½at², v² = u² + 2as and s = ½(u + v)t only when acceleration is constant.
A.1.8 Free fall
Free fall means motion under gravity only. Near Earth, g ≈ 9.8 m s⁻² downward.
A.1.9 Projectile motion
Horizontal velocity is constant. Vertical acceleration is downward. Time links the two components.
A.1.10 Relative motion
Relative motion depends on the observer’s frame of reference. Velocities may be added or subtracted depending on direction.
6. Readiness Checklist
Ready for the quiz?
If you understand the graph rules, key equations and common mistakes above,
you are ready to start the A.1 Kinematics Visual/Data Quiz.
Recommended time: 15–20 minutes
Focus: graphs, data, vectors, acceleration and projectile motion