HideShow resource information
View mindmap
  • P1abcd
    • P1a) Heating Houses
      • Energy always flows from a warmer body to a colder body
      • A thermogram uses colour to show temperature
        • When the temperature of a body increases, so does the average kinetic energy
      • Temperature is measured on an arbitrary scale. Heat is measure on an absolute scale.
      • Specific latent heat is the energy needed to melt or boil 1kg of the material.
        • It is measured in J/kg
        • Energy transferred = mass x SLH
        • When a substance changes state, energy is needed to break the bonds that hold molecules together
    • P1b) Keeping homes warm
      • Double glazing reduces energy loss by conduction - the gap between two pieces of gas is filled with gas or contains a vacuum.
      • Loft insulation reduces energy loss by conduction and convection
        • Insulation blocks have shiny foil on both sides to reduce energy transfer by radiation
      • density = mass x volume
        • Energy can be transferred by conduction or convection
          • Conduction is due to the transfer of kinetic energy, convection is when a gas expands when heated.
      • Energy efficiency is measured in Sankey diagrams
        • Payback time = cost of insulation / annual saving
        • Well instulated homes are energy efficient
        • Everything that transfers energu will waste some energy as heat to surroundings
    • P1c) A spectrum of waves
      • Wave speed = frequency x wavelength
      • The frequency order of waves is: Radio, Microwaves, Infrared, Visible, Ultraviolet, X-Ray, Gamma Ray
      • Diffraction depends on the size of the gap, a larger gap means less diffraction.
    • P1d) Lights and Lasers
      • Signals sent are almost instant
        • Each method has benefits and drawbacks
      • Laser light differs from white light as it is only made up of a single frequency
      • When the angle of refraction is 90, the AOI is called the critical angle
        • An endoscope uses light to see inside the body
          • Light passes alone optical fibres. The light is then reflected, which passes another set of fibres to an eyepiece or camera.
        • If the AOI is bigger than the CA, the light is reflected; this is TIR


No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Waves resources »