What is kinematics in IB Physics?

Kinematics is the study of motion without considering the forces causing the motion. It includes displacement, velocity and acceleration.

What are the SUVAT equations?

SUVAT equations describe motion with constant acceleration including v = u + at and s = ut + 1/2 at^2.

How do you solve kinematics problems?

Identify known variables, choose the correct SUVAT equation, substitute the values and solve step by step.

IB Physics Kinematics Explained | Formulas, Graphs & Examples

Complete IB Physics Kinematics Guide - Formulas Graphs Motion Equations

IB Physics Kinematics Explained

Kinematics is one of the most fundamental topics in IB Physics. According to the official IB Physics curriculum , students must understand displacement, velocity, acceleration and motion graphs to solve exam problems effectively.

What is Kinematics?

Kinematics is the branch of physics that describes how objects move. Instead of studying forces, kinematics focuses on measurable quantities such as displacement, velocity and acceleration.

Key Quantities in IB Physics Kinematics

Displacement

Displacement is the change in position of an object in a particular direction. Unlike distance, displacement is a vector quantity and includes direction.

Velocity

Velocity is the rate of change of displacement with time. It describes both speed and direction of motion.

Acceleration

Acceleration describes how quickly velocity changes with time. Positive acceleration increases velocity, while negative acceleration (deceleration) slows an object down.

Kinematics Interactive Explainer

Kinematics interactive explainer

Displacement is the straight-line change in position from start to finish — it has both magnitude and direction (it is a vector).

s = x_final − x_initial

Initial position (x₀) 10 m

Final position (x) 60 m

Displacement (s)

50m

Distance

50m

Direction

Forward +x

The car moved 50 m forward. Displacement equals distance here because it only moved in one direction.

Velocity = rate of change of displacement. Speed is its magnitude; velocity also tells you direction.

v = s / t (uniform motion)

Displacement (s) 100 m

Time (t) 5 s

Velocity (v)

20m/s

Speed (|v|)

20m/s

In km/h

72km/h

On a displacement–time graph, the slope = velocity. A steeper line means faster motion.

Acceleration is the rate of change of velocity. Positive = speeding up; negative = slowing down (deceleration).

a = (v − u) / t

Initial velocity (u) 0 m/s

Final velocity (v) 20 m/s

Time (t) 5 s

Acceleration (a)

4m/s²

Type

Accelerating

Δv

20m/s

The car speeds up from 0 to 20 m/s over 5 s. On a v–t graph, the slope is the acceleration.

The four SUVAT equations let you solve any uniform-acceleration problem. Set any three known values and instantly see the rest.

v = u + at

s = ut + ½at²

v² = u² + 2as

s = ½(u + v)t

Initial velocity (u) 5 m/s

Acceleration (a) 3 m/s²

Time (t) 4 s

Final velocity (v)

17m/s

Displacement (s)

44m

Avg velocity

11m/s

IB Physics Kinematics Equations

When acceleration is constant, the following SUVAT equations are used:

v = u + at

s = ut + ½at²

v² = u² + 2as

s = (u + v) / 2 × t

Velocity-Time Graph

In a velocity-time graph, slope represents acceleration and area under the graph represents displacement.

Kinematics Simulator

Physics Lab

Kinematics Simulator

1D Motion

Init. Velocity

0.0 m/s

Acceleration

2.0 m/s²

Duration

5 seconds

Distance

25.0 m

From ut

0.0 m

Final vel.

10.0 m/s

Avg vel.

5.0 m/s

Trajectory preview

0 m

Formula s = ut + ½at² = 25.0 m

Interactive IB Exam Solver

A car accelerates from 0 m/s at 3 m/s² for 4 seconds. Find the final velocity.

Common Mistakes Students Make

Confusing distance with displacement
Using the wrong SUVAT equation
Ignoring direction in velocity calculations
Misinterpreting velocity-time graphs

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