(AQA GCSE) PHYSICS PAPER 2 NOTES
, FORCES
Forces: Basics and Newton9s Laws
Forces Basics :
and Newton s 9
Laws :
A force is a push or pull that can
change the motion or shape of an
object. Forces are measured in
newtons (N). One newton is the force
needed to make a 1 kg mass accelerate
by 1 m/s².
Newton s First Law9
Law of Inertia
( )
An object will stay at rest or continue
moving at a constant velocity unless a
resultant force acts on it.
If the forces are balanced, the
motion doesn9t change.
If the forces are unbalanced, the
object will accelerate.
Newton s Second 9
Law
The acceleration of an object depends
on the resultant force and its mass.
F = ma
A bigger force ³ bigger
acceleration.
A bigger mass ³ smaller
acceleration for the same force.
AQA often asks about resultant force,
so emphasise:
Resultant force=sum of all forces acting
on the object
Remember, weight is a force! Weight = mass × gravitational field strength (W = mg). On Earth, the gravitational
field strength (g) is approximately 9.8 N/kg.
, FORCES
Forces Types and Effects AQA GCSE
: ( )
Contact Forces
Contact forces act when two objects are physically touching. Key examples:
Friction – opposes motion between two surfaces.
Tension – force in a stretched rope, cable, or string.
Normal contact force – acts perpendicular to a surface supporting an object.
TIP: AQA often tests these in free‐body diagrams.
Non-Contact Forces
These forces act without objects touching:
Gravity – attraction between masses.
Magnetic forces – between magnets or magnetic materials.
Electrostatic forces – between charged objects.
AQA frequently uses these in multiple‐choice and definition questions.
Hooke s Law ’
For a spring or elastic object:
F = kx
F = force applied (N)
k = spring constant (N/m)
x = extension (m)
Hooke’s Law applies only up to the elastic limit. Beyond this point, the object will not return to its original shape.
TIP: AQA loves graph questions showing the linear region vs. the limit of proportionality.
Moments
A moment is the turning effect of a force about a pivot.
Moment = force x perpendicular distance from pivot
Used to analyse:
levers
seesaws
balanced systems
For equilibrium:
Total clockwise moments = anticlockwise moments
This is a core AQA calculation.
Resultant Force
The resultant force is the single force that has the same effect as all the forces acting on an object combined.
Resultant force = 0 → object stays at rest or moves at constant velocity (Newton’s First Law).
Resultant force ≠ 0 → object accelerates (speed up, slow down, or change direction).
AQA often tests this with force diagrams and simple vector addition.
, WAVES
Waves: Types and Properties
What is a Wave?
A wave is a transfer of energy from one place to another without transferring matter. Particles oscillate, but they do not
travel with the wave.
NOTE: AQA tests this definition frequently.
Crest Trough
Top of a transverse Lowest point of the
wave wave
Wavelength
Distance between
Amplitude
crests Wave height from rest
Types of Waves (by medium)
Mechanical Waves
These waves require a medium (solid, liquid, or gas) to travel through.
Examples:
Sound waves (travel through air, liquids, and solids)
Water waves
Electromagnetic Waves
These waves do not need a medium and can travel through a vacuum.
Examples:
Light
Radio waves
Microwaves
X0rays
NOTE: AQA expects you to know that all electromagnetic waves travel at the same speed in a vacuum.
Types of Waves (by oscillation direction)
Transverse Waves
Oscillations are perpendicular to the direction of wave travel.
Examples:
Water waves
Electromagnetic waves
Waves on a string
Longitudinal Waves
Oscillations are parallel to the direction of wave travel.
Example:
Sound waves
Longitudinal waves have compressions and rarefactions, which AQA often tests.
Wave Properties
Wavelength (») 3 distance between two identical points on a wave (e.g., crest to crest).
Frequency (f) 3 number of waves passing a point per second (Hz).
Amplitude 3 maximum displacement from the rest position.
Wave speed (v) 3 how fast the wave travels.
These are linked by the wave equation:
v = f»
Waves: Behaviour and Applications
Reflection Refraction Diffraction
When a wave encounters a A wave changes speed and Waves can spread out or bend
boundary or surface, it direction when it passes from around obstacles or through
bounces back. Examples one medium to another, due openings. This effect is more
include echoes (sound to a change in its speed. This noticeable when the
reflection) and mirrors (light is why a spoon in a glass of wavelength is comparable to
reflection). water appears bent. the size of the obstacle or
opening.
, FORCES
Forces: Basics and Newton9s Laws
Forces Basics :
and Newton s 9
Laws :
A force is a push or pull that can
change the motion or shape of an
object. Forces are measured in
newtons (N). One newton is the force
needed to make a 1 kg mass accelerate
by 1 m/s².
Newton s First Law9
Law of Inertia
( )
An object will stay at rest or continue
moving at a constant velocity unless a
resultant force acts on it.
If the forces are balanced, the
motion doesn9t change.
If the forces are unbalanced, the
object will accelerate.
Newton s Second 9
Law
The acceleration of an object depends
on the resultant force and its mass.
F = ma
A bigger force ³ bigger
acceleration.
A bigger mass ³ smaller
acceleration for the same force.
AQA often asks about resultant force,
so emphasise:
Resultant force=sum of all forces acting
on the object
Remember, weight is a force! Weight = mass × gravitational field strength (W = mg). On Earth, the gravitational
field strength (g) is approximately 9.8 N/kg.
, FORCES
Forces Types and Effects AQA GCSE
: ( )
Contact Forces
Contact forces act when two objects are physically touching. Key examples:
Friction – opposes motion between two surfaces.
Tension – force in a stretched rope, cable, or string.
Normal contact force – acts perpendicular to a surface supporting an object.
TIP: AQA often tests these in free‐body diagrams.
Non-Contact Forces
These forces act without objects touching:
Gravity – attraction between masses.
Magnetic forces – between magnets or magnetic materials.
Electrostatic forces – between charged objects.
AQA frequently uses these in multiple‐choice and definition questions.
Hooke s Law ’
For a spring or elastic object:
F = kx
F = force applied (N)
k = spring constant (N/m)
x = extension (m)
Hooke’s Law applies only up to the elastic limit. Beyond this point, the object will not return to its original shape.
TIP: AQA loves graph questions showing the linear region vs. the limit of proportionality.
Moments
A moment is the turning effect of a force about a pivot.
Moment = force x perpendicular distance from pivot
Used to analyse:
levers
seesaws
balanced systems
For equilibrium:
Total clockwise moments = anticlockwise moments
This is a core AQA calculation.
Resultant Force
The resultant force is the single force that has the same effect as all the forces acting on an object combined.
Resultant force = 0 → object stays at rest or moves at constant velocity (Newton’s First Law).
Resultant force ≠ 0 → object accelerates (speed up, slow down, or change direction).
AQA often tests this with force diagrams and simple vector addition.
, WAVES
Waves: Types and Properties
What is a Wave?
A wave is a transfer of energy from one place to another without transferring matter. Particles oscillate, but they do not
travel with the wave.
NOTE: AQA tests this definition frequently.
Crest Trough
Top of a transverse Lowest point of the
wave wave
Wavelength
Distance between
Amplitude
crests Wave height from rest
Types of Waves (by medium)
Mechanical Waves
These waves require a medium (solid, liquid, or gas) to travel through.
Examples:
Sound waves (travel through air, liquids, and solids)
Water waves
Electromagnetic Waves
These waves do not need a medium and can travel through a vacuum.
Examples:
Light
Radio waves
Microwaves
X0rays
NOTE: AQA expects you to know that all electromagnetic waves travel at the same speed in a vacuum.
Types of Waves (by oscillation direction)
Transverse Waves
Oscillations are perpendicular to the direction of wave travel.
Examples:
Water waves
Electromagnetic waves
Waves on a string
Longitudinal Waves
Oscillations are parallel to the direction of wave travel.
Example:
Sound waves
Longitudinal waves have compressions and rarefactions, which AQA often tests.
Wave Properties
Wavelength (») 3 distance between two identical points on a wave (e.g., crest to crest).
Frequency (f) 3 number of waves passing a point per second (Hz).
Amplitude 3 maximum displacement from the rest position.
Wave speed (v) 3 how fast the wave travels.
These are linked by the wave equation:
v = f»
Waves: Behaviour and Applications
Reflection Refraction Diffraction
When a wave encounters a A wave changes speed and Waves can spread out or bend
boundary or surface, it direction when it passes from around obstacles or through
bounces back. Examples one medium to another, due openings. This effect is more
include echoes (sound to a change in its speed. This noticeable when the
reflection) and mirrors (light is why a spoon in a glass of wavelength is comparable to
reflection). water appears bent. the size of the obstacle or
opening.
