Choose an exam and explore concepts through visual explanations, topic maps and revision checks. Open the full chapter notes whenever you need more detail.
THE VISUAL LEARNING STUDIO
See the idea. Understand the connection.
35 visual explanations across 29 chapters, with topic maps throughout the library.
The chapter index will grow as additional notes are prepared. Chapters shown here are a learning collection, not a claim that the entire exam syllabus is complete.
SEE IT. CONNECT IT. EXPLAIN IT.
Understand the chapter visually
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Study the expanded notes and the credited detailed textbook lessons. The current chapter index covers core topics; it is not a claim of exhaustive coverage of every examination syllabus. Check the official syllabus and primary references.
Units, Vectors and Motion — lesson overview
Units and dimensions
A physical measurement combines a numerical value with a unit. The SI base units include metre, kilogram, and second for length, mass, and time.
Dimensions describe the type of physical quantity in terms of base quantities. Speed has dimension L T⁻¹; acceleration has L T⁻².
Dimensional consistency is necessary for a valid physical equation but does not prove it is the correct physical law or determine every numerical constant.
Distance, displacement, speed and velocity
Distance is path length, a scalar. Displacement is change in position, a vector. Their magnitudes need not be equal.
Average speed = total distance ÷ elapsed time. Average velocity = displacement ÷ elapsed time. A completed round trip can have positive average speed and zero average velocity.
Acceleration is the rate of change of velocity. It can result from a change in speed, direction, or both; uniform circular motion is a familiar example of changing direction.
Constant-acceleration example
For motion along a straight line with constant acceleration, v = u + at and s = ut + ½at², using a consistent sign convention.
Starting from rest with a = 2 m s⁻² for 5 s gives v = 10 m s⁻¹ and displacement s = 25 m.
These equations do not apply unchanged to arbitrary variable acceleration. Identify the assumptions before substituting values.
