AQA Combined Science Physics - Paper 1 Knowledge

• Function and colour of the earth wire

  Carry excess current from the live wire and blow the fuse if needed.

  Yellow and Green
• State the unit for charge

  Coulombs
• Why is the current the same everywhere in a series circuit

  There is only one route for current to flow
• What is the change of state from a gas to a liquid

  Condensing
• State the unit for mass

  KG / Kilogram
• What is a use of beta radiation

  Monitoring paper thickness
• How are particles arranged in a solid

  All particles in rows, touching
• What is the change of statefrom a liquid to a gas

  Evaporating
• Define current

  The rate of flow of charge of electrons
• What type of transformer is used to increase the potential difference

  Step-up transformers
• What is the function if a diode

  It only allows current to flow in one direction
• What is the change of state from solid to liquid

  Melting
• What is the change of state from a liquid to a solid

  Freezing
• How are particles arranged in a gas

  Random arrangement, widely spaced
• State the unit for frequency

  Hz / Hertz
• What equation links current, potential difference and power

  P = IV / Power = current x resistance
• Describe the strength of forces between particles in a gas

  Weak
• Describe the structure of a beta particle

  An electron
• Why is it useful that water has a high specific heat capacity

  It can store a lot of energy without causing a huge change in temperature
• What is the range in air for beta radiation

  Roughly a metre
• Which material cannot be penetrated by a beta particle

  A few cm of aluminium
• State the equation for gravitational potential energy

  Ep = m x g x h // Gravitational Potential = mass x gravity x height
• Why is coal more reliable than solar or wind

  Coal is available all the time. Solar only works during the day and wind only works on a windy enough day
• What is the national grid

  A system of cables and transformers, linking Power Stations to the consumers
• Compare finite and renewable sources of energy

  Renewable - can be replenished, made faster than they are used

  Finite - used faster than they are being made
• What is a use of alpha radiation

  Smoke Alarms
• State the equation that links charge, current and time

  Q=IT // Charge = current x time
• Discuss the changes occurring as a ball is dropped from a height

  The gravitational potential store of the ball decreases, and the kinetic energy store of the ball increases
• State the equation that links efficiency, total energy and useful energy

  Efficiency = useful energy output divided by total energy input
• How do particles move in a liquid

  Particles move around eachother
• Describe the nuclear atom model

  A positive nucleus in the centre with negative electrons orbiting it.
• What is the definition of internal energy

  The total energy that its particles have and their kinetic AND potential stores
• State the frequency and potential difference of mains electricity

  Frequency is 50Hz and the mains is 230v
• What is specific latent heat of fusion

  The amount of energy needed to change 1kg of a substance from a solid to a liquid
• What is the function of step-down transformers

  To decrease the potential difference for domestic use
• Which material cannot be penetrated by a gamma wave

  Very thick lead
• How is gas pressure caused

  The gas particles collide with the sides of their container, which applies a force to the area
• State the unit for resistance

  Ohms (you know how to draw it)
• Discuss the changes occurring when coal is burnt to heat water, using ideas about energy stores

  The chemical store in the coal decreases, whilst the thermal store of the water increases
• What is the change of state from a solid to a gas

  Sublimation