AQA GCSE Physics - Paper 2 with ans
What are vectors? - Ans>>Quantities that have a magnitude and a direction
What are scalars? - Ans>>Quantities that only have a magnitude
Examples of vectors - Ans>>Force
Velocity
Displacement
Acceleration
Momentum
Examples of scalars - Ans>>Speed
Distance
Mass
Temperature
Time
What are contact forces? - Ans>>Forces that act when two objects are
touching
What are non-contact forces? - Ans>>Forces that act without the need for
two objects to be touching
Examples of contact forces - Ans>>Friction
Air resistance
Tension in ropes
Normal contact force
Examples of non-contact forces - Ans>>Magnetic force
Gravitational force
Electrostatic force
What is mass? - Ans>>The amount of material an object is made of
It is the same value everywhere
Measured using a mass balance
What is weight? - Ans>>The force acting on an object due to gravity
,It depends on the strength of the gravitational field at the location of the
object
Measured using a calibrated spring balance - newtonmeter
Equation for Weight - Ans>>Weight (N) = Mass (kg) x Gravitational Field
Strength (N/kg)
W=mg
What is weight directly proportional to? - Ans>>Mass
What are free body diagrams? - Ans>>Diagrams that show all the forces
acting on an object
What is the minimum number of forces acting on an object in real situations?
- Ans>>At least 2 forces
What is the resultant force? - Ans>>The single force that replaces multiple
forces acting at a single point
How is work done? - Ans>>When a force moves an object through a
distance, energy is transferred and work is done on the object
Equation for 'Work Done' - Ans>>Work done (J) = Force (N) x Distance (m)
W=Fs
What is 1J equal to? - Ans>>1Nm
What could happen when you apply a force to an object? - Ans>>It may
stretch, compress or bend
What happens when an object is inelastically deformed? - Ans>>The object
won't return to its original shape and length after the force has been
removed
Equation for Force 1 - Ans>>Force (N) = Spring Constant (N/m) x Extension
(m)
F=ke
What is extension directly proportional to? - Ans>>The force applied
F∝e
The stiffer the spring... - Ans>>...The greater the spring constant
What is the limit of proportionality? - Ans>>The point at which extension is
no longer directly proportional to force
,Equation for 'Moments' - Ans>>Moment of a force (Nm) = Force (N) x
Distance (m)
M=Fd
What is a moment? - Ans>>The turning effect of a force
When will an object not turn? - Ans>>When the object is balanced - the total
anticlockwise moment equals the total clockwise moment about a pivot
What affects the size of a moment? - Ans>>1) The size of the force applied -
a larger force will produce a larger moment
2) The perpendicular distance from the pivot to the line of action of the force
- any angle smaller than 90° will result in a smaller distance, thus a smaller
moment
What do levers do? - Ans>>They increase the distance from the pivot at
which the force is applied
Do levers make it easier or harder to do work? - Ans>>Easier to do work
What are gears and what do they do? - Ans>>Circular discs with 'teeth'
around their edges
Their teeth interlock so that turning one causes another to turn in the
opposite direction
They are used to transmit the rotational effect of a force from one place to
another
What is pressure? - Ans>>The force per unit area
Equation for Pressure - Surface of a fluid - Ans>>Pressure (Pa) = Force
normal to a surface (N) / Area of that surface (m²)
p=F/A
What is the pressure of a fluid? - Ans>>A force is exerted normal (at right
angles) to any surface in contact with the fluid
What is density? - Ans>>A measure of the 'compactness' of a substance
Equation for Pressure - Liquid - Ans>>Pressure (Pa) = Height of the column
of liquid (the depth)(m) x Density of the liquid (kg/m³) x Gravitational field
strength (N/kg)
p=hρg
, What is upthrust? - Ans>>The force exerted on the bottom of the object is
larger than the force acting on the top of the object - the resultant force
upwards on an object when it is submerged in water
What is upthrust equal to? - Ans>>The weight of fluid that has been
displaced by the object
Why do objects float? - Ans>>The upthrust of the object is equal to the
object's weight, thus the force balances
It has a low density
Why do objects sink? - Ans>>The object's weight is more than the upthrust
It has a high density
Low density - Ans>>If an object is less dense than the fluid it is placed in, it
weighs less than the equivalent volume of fluid
It will displace a volume of fluid that is equal to its weight before it is
completely submerged
High density - Ans>>If an object is denser than the fluid it is placed in, it will
be unable to displace enough fluid to equal its weight, therefore its weight
will be larger
How do submarines make use of upthrust? - Ans>>To sink, large tanks are
filled with water to increase the weight of the submarine so that it is more
than the upthrust
To float, the tanks are filled with compressed air to reduce the weight so that
it is less than the upthrust
What is atmospheric pressure? - Ans>>A layer of air that surrounds Earth
It's created on a surface when air molecules collide with the surface
What is atmospheric pressure inversely proportional to? - Ans>>Altitude
(height above Earth)
If the altitude increases, atmospheric pressure decreases and becomes less
dense
What else happens when altitude increases? - Ans>>There are fewer air
molecules above a surface as the height increases, therefore the weight of
the air above it (which contributes to atmospheric pressure) decreases
What is distance? - Ans>>How far an object has moved
What are vectors? - Ans>>Quantities that have a magnitude and a direction
What are scalars? - Ans>>Quantities that only have a magnitude
Examples of vectors - Ans>>Force
Velocity
Displacement
Acceleration
Momentum
Examples of scalars - Ans>>Speed
Distance
Mass
Temperature
Time
What are contact forces? - Ans>>Forces that act when two objects are
touching
What are non-contact forces? - Ans>>Forces that act without the need for
two objects to be touching
Examples of contact forces - Ans>>Friction
Air resistance
Tension in ropes
Normal contact force
Examples of non-contact forces - Ans>>Magnetic force
Gravitational force
Electrostatic force
What is mass? - Ans>>The amount of material an object is made of
It is the same value everywhere
Measured using a mass balance
What is weight? - Ans>>The force acting on an object due to gravity
,It depends on the strength of the gravitational field at the location of the
object
Measured using a calibrated spring balance - newtonmeter
Equation for Weight - Ans>>Weight (N) = Mass (kg) x Gravitational Field
Strength (N/kg)
W=mg
What is weight directly proportional to? - Ans>>Mass
What are free body diagrams? - Ans>>Diagrams that show all the forces
acting on an object
What is the minimum number of forces acting on an object in real situations?
- Ans>>At least 2 forces
What is the resultant force? - Ans>>The single force that replaces multiple
forces acting at a single point
How is work done? - Ans>>When a force moves an object through a
distance, energy is transferred and work is done on the object
Equation for 'Work Done' - Ans>>Work done (J) = Force (N) x Distance (m)
W=Fs
What is 1J equal to? - Ans>>1Nm
What could happen when you apply a force to an object? - Ans>>It may
stretch, compress or bend
What happens when an object is inelastically deformed? - Ans>>The object
won't return to its original shape and length after the force has been
removed
Equation for Force 1 - Ans>>Force (N) = Spring Constant (N/m) x Extension
(m)
F=ke
What is extension directly proportional to? - Ans>>The force applied
F∝e
The stiffer the spring... - Ans>>...The greater the spring constant
What is the limit of proportionality? - Ans>>The point at which extension is
no longer directly proportional to force
,Equation for 'Moments' - Ans>>Moment of a force (Nm) = Force (N) x
Distance (m)
M=Fd
What is a moment? - Ans>>The turning effect of a force
When will an object not turn? - Ans>>When the object is balanced - the total
anticlockwise moment equals the total clockwise moment about a pivot
What affects the size of a moment? - Ans>>1) The size of the force applied -
a larger force will produce a larger moment
2) The perpendicular distance from the pivot to the line of action of the force
- any angle smaller than 90° will result in a smaller distance, thus a smaller
moment
What do levers do? - Ans>>They increase the distance from the pivot at
which the force is applied
Do levers make it easier or harder to do work? - Ans>>Easier to do work
What are gears and what do they do? - Ans>>Circular discs with 'teeth'
around their edges
Their teeth interlock so that turning one causes another to turn in the
opposite direction
They are used to transmit the rotational effect of a force from one place to
another
What is pressure? - Ans>>The force per unit area
Equation for Pressure - Surface of a fluid - Ans>>Pressure (Pa) = Force
normal to a surface (N) / Area of that surface (m²)
p=F/A
What is the pressure of a fluid? - Ans>>A force is exerted normal (at right
angles) to any surface in contact with the fluid
What is density? - Ans>>A measure of the 'compactness' of a substance
Equation for Pressure - Liquid - Ans>>Pressure (Pa) = Height of the column
of liquid (the depth)(m) x Density of the liquid (kg/m³) x Gravitational field
strength (N/kg)
p=hρg
, What is upthrust? - Ans>>The force exerted on the bottom of the object is
larger than the force acting on the top of the object - the resultant force
upwards on an object when it is submerged in water
What is upthrust equal to? - Ans>>The weight of fluid that has been
displaced by the object
Why do objects float? - Ans>>The upthrust of the object is equal to the
object's weight, thus the force balances
It has a low density
Why do objects sink? - Ans>>The object's weight is more than the upthrust
It has a high density
Low density - Ans>>If an object is less dense than the fluid it is placed in, it
weighs less than the equivalent volume of fluid
It will displace a volume of fluid that is equal to its weight before it is
completely submerged
High density - Ans>>If an object is denser than the fluid it is placed in, it will
be unable to displace enough fluid to equal its weight, therefore its weight
will be larger
How do submarines make use of upthrust? - Ans>>To sink, large tanks are
filled with water to increase the weight of the submarine so that it is more
than the upthrust
To float, the tanks are filled with compressed air to reduce the weight so that
it is less than the upthrust
What is atmospheric pressure? - Ans>>A layer of air that surrounds Earth
It's created on a surface when air molecules collide with the surface
What is atmospheric pressure inversely proportional to? - Ans>>Altitude
(height above Earth)
If the altitude increases, atmospheric pressure decreases and becomes less
dense
What else happens when altitude increases? - Ans>>There are fewer air
molecules above a surface as the height increases, therefore the weight of
the air above it (which contributes to atmospheric pressure) decreases
What is distance? - Ans>>How far an object has moved
