AQA GCSE PHYSICS PAPER 1 PRACTICE SOLUTION STUDY SHEET QUESTIONS AND DETAILED ANSWERS

AQA GCSE PHYSICS PAPER 1 PRACTICE
SOLUTION STUDY SHEET QUESTIONS AND
DETAILED ANSWERS

●● How is energy transferred?
Answer: 1) Mechanically - force doing work
2) Electrically - work done by moving charges
3) Heating/Radiation - light, sound


●● How can work be done?
Answer: When a current flows or by a force moving an object any
direction.


●● What is the conservation of energy principle?
Answer: Energy can be transferred usefully, or stored or dissipated
(wasted energy), but can never be created or destroyed


●● What is conduction?
Answer: The process where vibrating particles transfer energy to
neighbouring particles
Energy is transferred to thermal stores of the object - this energy is
shared across the kinetic energy stores

,●● What is thermal conductivity?
Answer: A measure of how quickly energy is transferred through a
material via conduction


●● What is convection?
Answer: Where energetic particles move away from hotter to cooler
regions
Energy is transferred to the thermal energy stores of the object and is
shared across the kinetic stores


●● What do radiators create?
Answer: Convection currents


●● Convection currents - process
Answer: 1) Energy is transferred from the radiator to the nearby air
particles by conduction
2) The air by the radiator becomes warmer and less dense as the particles
move quicker
3) The warm air rises and displaces the cooler air, which is then heated
by the radiator
4) The previously heated air transfers energy to the surroundings - the air
cools, becomes denser and sinks


●● What does lubrication do?

,Answer: Reduce frictional forces


●● What does insulation do?
Answer: Reduce the rate of energy transfer by heating


●● Thermal insulation techniques
Answer: 1) Cavity walls - made up of an inner and outer wall with an air
gap in the middle - the air gap reduces the amount of energy transferred
by conduction through the walls
2) Cavity wall insulators - the air gap is filled with foam also reduces
energy transfer by convection in the wall cavity
3) Loft insulation - reduces convection currents being created in lofts
4) Double-glazed windows - air gap between two sheets of glass that
prevent energy transfer by conduction through the windows
5) Draught excluders - reduce energy transfers by convection around
doors and windows


●● How do you improve efficiency?
Answer: 1) Lubrication
2) Insulation
3) Making objects more streamlined


●● Efficiency - energy transfer equation

, Answer: Useful output energy transfer divided by total input energy
transfer


●● Is any device 100% efficienct?
Answer: No


●● Where is wasted energy usually transferred?
Answer: Thermal energy stores


●● How do thick walls prevent energy losses through heating?
Answer: They're made from a material with a low thermal conductivity -
the thicker the walls, the lower the thermal conductivity, the slower the
rate of energy transfer


●● Fossil fuels (coal, oil, natural gas)
Answer: Non-renewable
Cause acid rain
Cause global warming
Reliable currently - they are finite, so they will run out eventually
Coal mining ruins the landscape
Oil spillages cause serious environmental problems


●● Energy resources used for transport