PHYSICS AQA UNIT 1 EXAM 2025
QUESTIONS AND ANSWERS
All objects emit infrared radiation. - ANS Which objects emit infrared radiation?
Infrared radiation is energy transfer by electromagnetic waves. - ANS Define: Infrared
radiation
transfer of energy by electromagnetic waves - ANS Define radiation
Conduction, Convection, Infrared Radiation - ANS What are the three ways in which energy is
transferred?
the more infrared radiation it emits in a given time. - ANS Complete the sentence:
The hotter an object is...
Dark, matt surfaces - ANS What type of surfaces are good absorbers and emitters of infrared
radiation?
Light, shiny surfaces - ANS What type of surfaces are good reflectors of infrared radiation?
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,Light, shiny surfaces - ANS What type of surfaces are poor absorbers and emitters of infrared
radiation?
Solids have a Fixed shape.
Particles are held together in a fixed position due to the Strong force of attraction between
particles.
They vibrate in a fixed position.
They cannot be compressed because the particles are already as close as possible.
They have the least energy. - ANS Properties of a solid
Liquids fill/take the shape of a container. Each particle can slide past each other because the
force of attraction is weaker. They cannot be compressed because the particles are already as
close as can be. They have more energy than solids. - ANS Properties of Liquids
Gases do not have a fixed shape. They are free to move around because there are no force of
attraction between particles. They can fill a container and can be compressed because there
are spaces between particles. They have the most energy because they are free to move. -
ANS Properties of Gases
Condensation - ANS Gas -> Liquid
Boiling - ANS Liquid-> Gas
Freezing - ANS Liquid-> Solid
Melting - ANS Solid-> Liquid
The process where vibrating particles pass on their extra kinetic energy to neighbouring
particles. - ANS Define: Conduction
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, Conductors: dense solids and metals - ANS In what materials does conduction happen
fastest?
They have free electrons that move about randomly in the metal and transfer energy. -
ANS Why are metals good conductors?
Insulators: materials that have large spaces between their particles and non-metals. - ANS In
what materials does conduction happen the slowest?
Their electrons are held in the atoms.
Energy transfer only takes place when atoms vibrate and shake each other.
This is less effective than conduction in metals. - ANS Why are non-metals good insulators?
.The air/(water) next to the heater/(place) is heated and so the particles gain energy..
This causes the air/(water) to expand and become less dense. Hot air/(water) rises and cold
air/(water) falls to take its place. - ANS Explain convection current in hot places e.g heating a
room with a heater
. The air/(water) next to the fridge/(place) is cooled and so the particles lose energy. This causes
to contract and become more dense. Cold air/(water) falls and hot air/(water) rises to take its
place - ANS Explain convection current in cold places e.g a fridge
The gas particles lose heat energy, so the gas cools. The particles lose kinetic energy si it moves
around less. The attractive forces pulls the particles together. The particles are so close
together that they form a liquid. - ANS What happens in the process of condensation?
Reduce the temperature of the surface that the gas touches
Reduce temperature of gas
Reduce wind/draft - ANS How can condensation on a surface be increased?
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QUESTIONS AND ANSWERS
All objects emit infrared radiation. - ANS Which objects emit infrared radiation?
Infrared radiation is energy transfer by electromagnetic waves. - ANS Define: Infrared
radiation
transfer of energy by electromagnetic waves - ANS Define radiation
Conduction, Convection, Infrared Radiation - ANS What are the three ways in which energy is
transferred?
the more infrared radiation it emits in a given time. - ANS Complete the sentence:
The hotter an object is...
Dark, matt surfaces - ANS What type of surfaces are good absorbers and emitters of infrared
radiation?
Light, shiny surfaces - ANS What type of surfaces are good reflectors of infrared radiation?
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 1
,Light, shiny surfaces - ANS What type of surfaces are poor absorbers and emitters of infrared
radiation?
Solids have a Fixed shape.
Particles are held together in a fixed position due to the Strong force of attraction between
particles.
They vibrate in a fixed position.
They cannot be compressed because the particles are already as close as possible.
They have the least energy. - ANS Properties of a solid
Liquids fill/take the shape of a container. Each particle can slide past each other because the
force of attraction is weaker. They cannot be compressed because the particles are already as
close as can be. They have more energy than solids. - ANS Properties of Liquids
Gases do not have a fixed shape. They are free to move around because there are no force of
attraction between particles. They can fill a container and can be compressed because there
are spaces between particles. They have the most energy because they are free to move. -
ANS Properties of Gases
Condensation - ANS Gas -> Liquid
Boiling - ANS Liquid-> Gas
Freezing - ANS Liquid-> Solid
Melting - ANS Solid-> Liquid
The process where vibrating particles pass on their extra kinetic energy to neighbouring
particles. - ANS Define: Conduction
Copyright ©2025 BRIGHTSTARS ALL RIGHTS RESERVED 2
, Conductors: dense solids and metals - ANS In what materials does conduction happen
fastest?
They have free electrons that move about randomly in the metal and transfer energy. -
ANS Why are metals good conductors?
Insulators: materials that have large spaces between their particles and non-metals. - ANS In
what materials does conduction happen the slowest?
Their electrons are held in the atoms.
Energy transfer only takes place when atoms vibrate and shake each other.
This is less effective than conduction in metals. - ANS Why are non-metals good insulators?
.The air/(water) next to the heater/(place) is heated and so the particles gain energy..
This causes the air/(water) to expand and become less dense. Hot air/(water) rises and cold
air/(water) falls to take its place. - ANS Explain convection current in hot places e.g heating a
room with a heater
. The air/(water) next to the fridge/(place) is cooled and so the particles lose energy. This causes
to contract and become more dense. Cold air/(water) falls and hot air/(water) rises to take its
place - ANS Explain convection current in cold places e.g a fridge
The gas particles lose heat energy, so the gas cools. The particles lose kinetic energy si it moves
around less. The attractive forces pulls the particles together. The particles are so close
together that they form a liquid. - ANS What happens in the process of condensation?
Reduce the temperature of the surface that the gas touches
Reduce temperature of gas
Reduce wind/draft - ANS How can condensation on a surface be increased?
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