GRADE 11
PHYSICAL SCIENCES
MECHANICS
CONDENSED EXAM REVISION NOTES
South African CAPS study guide
Inside this guide
• Vectors and scalars
• Motion in one dimension
• Newton's laws of motion
• Momentum and impulse
• Work, energy and power
• Formula summary and practice questions
Clear explanations • Essential equations • Exam reminders
Use alongside your prescribed textbook, class notes and current CAPS assessment guidelines.
Grade 11 Physical Sciences | Mechanics Page 1
, HOW TO USE THESE NOTES
These notes are a condensed revision aid. Learn the definitions, practise choosing equations, show every calculation
step and check units and directions. Confirm the exact scope of your examination with your teacher and the current
CAPS curriculum.
General calculation method: (1) Write the given values, (2) identify the unknown, (3) convert to SI units, (4) choose an
appropriate equation, (5) substitute values, (6) calculate, and (7) give the unit and direction where relevant.
1. VECTORS AND SCALARS
1.1 Scalars
A scalar is a physical quantity with magnitude only. Examples include distance, speed, time, mass, temperature and
energy.
1.2 Vectors
A vector is a physical quantity with both magnitude and direction. Examples include displacement, velocity,
acceleration, force and momentum.
Scalar quantity Related vector quantity
Distance Displacement
Speed Velocity
— Acceleration
— Force
Energy Momentum (not a direct pair)
1.3 Resultant vectors
The resultant is the single vector that has the same effect as two or more vectors acting together.
Same direction: R = A + B
Opposite directions: R = |A − B|, in the direction of the larger vector
Perpendicular vectors: R = √(A² + B²)
Exam reminder: Include direction in a vector answer. For vectors at other angles, use an appropriate component or
scale-diagram method taught in class.
2. MOTION IN ONE DIMENSION
2.1 Key definitions
Quantity Meaning SI unit
Distance Total length of the path travelled m
Displacement Change in position, with direction m
Speed Rate of change of distance m·s■¹
Velocity Rate of change of displacement m·s■¹
Acceleration Rate of change of velocity m·s■²
2.2 Average quantities
Average speed = total distance ÷ total time
Grade 11 Physical Sciences | Mechanics Page 2
PHYSICAL SCIENCES
MECHANICS
CONDENSED EXAM REVISION NOTES
South African CAPS study guide
Inside this guide
• Vectors and scalars
• Motion in one dimension
• Newton's laws of motion
• Momentum and impulse
• Work, energy and power
• Formula summary and practice questions
Clear explanations • Essential equations • Exam reminders
Use alongside your prescribed textbook, class notes and current CAPS assessment guidelines.
Grade 11 Physical Sciences | Mechanics Page 1
, HOW TO USE THESE NOTES
These notes are a condensed revision aid. Learn the definitions, practise choosing equations, show every calculation
step and check units and directions. Confirm the exact scope of your examination with your teacher and the current
CAPS curriculum.
General calculation method: (1) Write the given values, (2) identify the unknown, (3) convert to SI units, (4) choose an
appropriate equation, (5) substitute values, (6) calculate, and (7) give the unit and direction where relevant.
1. VECTORS AND SCALARS
1.1 Scalars
A scalar is a physical quantity with magnitude only. Examples include distance, speed, time, mass, temperature and
energy.
1.2 Vectors
A vector is a physical quantity with both magnitude and direction. Examples include displacement, velocity,
acceleration, force and momentum.
Scalar quantity Related vector quantity
Distance Displacement
Speed Velocity
— Acceleration
— Force
Energy Momentum (not a direct pair)
1.3 Resultant vectors
The resultant is the single vector that has the same effect as two or more vectors acting together.
Same direction: R = A + B
Opposite directions: R = |A − B|, in the direction of the larger vector
Perpendicular vectors: R = √(A² + B²)
Exam reminder: Include direction in a vector answer. For vectors at other angles, use an appropriate component or
scale-diagram method taught in class.
2. MOTION IN ONE DIMENSION
2.1 Key definitions
Quantity Meaning SI unit
Distance Total length of the path travelled m
Displacement Change in position, with direction m
Speed Rate of change of distance m·s■¹
Velocity Rate of change of displacement m·s■¹
Acceleration Rate of change of velocity m·s■²
2.2 Average quantities
Average speed = total distance ÷ total time
Grade 11 Physical Sciences | Mechanics Page 2
