Science

• Convection


  1. Fluids particles are spread apart, as it gains kinetic energy,the particles more energetic,will move further away from the heat

  2. The particles near the heat would gain energy, spread out, becoming less dense then they rise above while colder particles sink down and take their place

  3. The cycle continues as the cold particles heat up and hot particles cool down sinking back down

  4. To stop convection currents, we stop the free flow of fluids
• Conduction

  Only the energy is transferred
• Convection

  The particles also move
• Conduction


  1. The transfer of heat through a solid

  2. It is done through the vibration of particles transferring energy to particles near them

  More heat - the faster particles vibrate - faster heat is transferred equally
• Conduction


  • This way of transferring energy is used by solid because solid particles are tightly packed and have high density causing vibrations which then results in the transfer of heat energy
• Thermal conductivity


  How well the energy is transferred in objects
• Thermal energy is measured in joules and it always move from warmer to colder until the object has the same temperature to its surroundings
• Radiation

  1. Transfer of energy without particles but by using waves

  2. The hotter the object, the more infrared radiation is produced

  3. It can transfer energy through solids, liquid and gas

  4. Solids: transparent materials,opaque,reflective,translucent

  5. Radiation also cause particles to vibrate more when radiation transfer energy /comes in contact with the particles within the solid material and it increases in heat energy leading to increase of kinetic energy, making it vibrate
• Electromagnetic spectrum

  • Radio (low frequency but big wavelength)
  • Microwaves
  • Infrared
  • Visible light
  • Ultra Violet
  • X-rays
  • Gamma rays ( high frequency but small wavelength) most damaging
• Transverse waves


  Oscillate perpendicular to the direction of energy transfer (moving up and down)
• Frequency


  The number waves
• Wavelength


  The length of each wave
• As the frequency increase


  The wavelength decrease
• We can only see visible lights
• Colors of visible light

  • red
  • orange
  • yellow
  • green
  • blue
  • indigo
  • violet
• Absorption, transmission, reflection


  When Electromagnet waves hit an object, it is either absorbed, transmitted(able to pass through) or reflected depending on the characteristics of the material or waves
• Factors affecting reaction of waves


  • Frequency
  • Material properties
  • Angle of incidence