Actual 2024 AQA A-level PHYSICS
7408/2 Paper 2 Merged Question Paper +
Mark Scheme + Insert
Describe the graph of temperature against energy supplied to an object.
Linear increase, except in the regions where the object changes state; at this
stage, the energy is being put into breaking the bonds between the atoms
(potential energy) as opposed to raising the temperature (kinetic energy).
Define internal energy.
the sum of the random distribution of kinetic and potential energies associated
with the particles in a system
Brainpower
Read More
Describe evaporation.
,when only the particles on the surface of a liquid have sufficient energy to
become a gas
Give the names for the transfers between the physical states.
melting, boiling, condensing, freezing, sublimation
Describe the difference between the particles in solids, liquids and gases, and how they
behave as the temperature increases.
They are in a regular repeating arrangement for solids, then they are touching
but less regular for a liquid, and then far apart for a gas. The more heat energy
is applied, the more the particles vibrate and crucially the more their MEAN
kinetic energy increases. When sufficient heat energy is applied, physical state
changes can occur.
When can the internal energy of a system increase?
when energy is transferred to the system or when work is done on it
first law of thermodynamics
the change of the internal energy of an object is equal to the total energy
transfer due to work done and heating (this is an application of the
conservation of energy)
What is absolute zero?
, 0 Kelvin or around -273 C, the theoretical lowest possible temperature, when
the particles have no kinetic energy
How can we convert from Celcius to Kelvin?
add 273
How can we convert from Kelvin to Celcius?
subtract 273
Define specific heat capacity.
the energy needed to raise the temperature of 1kg of a substance by 1 degree
Kelvin (or 1 degree Celsius as both have the same width) without a change of
state
Define specific latent heat.
the energy needed to change the state of 1kg of a material without a change of
temperature
What is the specific latent heat called from a solid to a liquid or vice versa?
specific latent heat of fusion
What is the specific latent heat called from a gas to a liquid or vice versa?
specific latent heat of vaporisation
Are changes of state physical or chemical changes? Are they reversible?
they are physical, and so yes, they are reversible
7408/2 Paper 2 Merged Question Paper +
Mark Scheme + Insert
Describe the graph of temperature against energy supplied to an object.
Linear increase, except in the regions where the object changes state; at this
stage, the energy is being put into breaking the bonds between the atoms
(potential energy) as opposed to raising the temperature (kinetic energy).
Define internal energy.
the sum of the random distribution of kinetic and potential energies associated
with the particles in a system
Brainpower
Read More
Describe evaporation.
,when only the particles on the surface of a liquid have sufficient energy to
become a gas
Give the names for the transfers between the physical states.
melting, boiling, condensing, freezing, sublimation
Describe the difference between the particles in solids, liquids and gases, and how they
behave as the temperature increases.
They are in a regular repeating arrangement for solids, then they are touching
but less regular for a liquid, and then far apart for a gas. The more heat energy
is applied, the more the particles vibrate and crucially the more their MEAN
kinetic energy increases. When sufficient heat energy is applied, physical state
changes can occur.
When can the internal energy of a system increase?
when energy is transferred to the system or when work is done on it
first law of thermodynamics
the change of the internal energy of an object is equal to the total energy
transfer due to work done and heating (this is an application of the
conservation of energy)
What is absolute zero?
, 0 Kelvin or around -273 C, the theoretical lowest possible temperature, when
the particles have no kinetic energy
How can we convert from Celcius to Kelvin?
add 273
How can we convert from Kelvin to Celcius?
subtract 273
Define specific heat capacity.
the energy needed to raise the temperature of 1kg of a substance by 1 degree
Kelvin (or 1 degree Celsius as both have the same width) without a change of
state
Define specific latent heat.
the energy needed to change the state of 1kg of a material without a change of
temperature
What is the specific latent heat called from a solid to a liquid or vice versa?
specific latent heat of fusion
What is the specific latent heat called from a gas to a liquid or vice versa?
specific latent heat of vaporisation
Are changes of state physical or chemical changes? Are they reversible?
they are physical, and so yes, they are reversible
