CONDUCTION

THERMAL ENERGY- CONDUCTION

conduction is the process of thermal energy transfer without any flow of the material medium

• different materials conduct heat at different rates
  

metals(iron,copper,silver) are generally good conductors of heat while non metals(wood,plastic,glass) are poor conductors of heat

why? because conductors & insulator have different mechanisms to transfer thermal energy

conduction

• all solids(metals & non metals) are made up of atoms and molecules
  
• (DIFFERENCE) metals contain free electrons which move randomly between atoms and molecules while non metals do not contain such free electrons
  
• When a metal rod(conductor)and a non-metal rod are heated from one end, the particles at the hot end vibrates and collides with neighbouring particles, causing them to vibrate and thus the kinetic energy at the hot end is transferred on
  
• The transfer of energy through the atoms and molecules vibration is quite slow.
  
  conduction in metals

• However, metals have free electrons in them which allows thermal energy to be transferred by free electron diffusion

• When a metal rod is heated(conductor), the free electrons gains kinetic energy, and thus move faster and collide randomly with the particles in the cooler region of the metal and transfer kinetic energy to them
  
  
• Therefore, metals are better conductors than non metals :)
  

*thermal energy can also be conducted in liquid and gas.however,because the particles are spaced further apart in liquid and gases than in solids, the collisions between the particles are less frequent and thus the transfer of kinetic energy between particles is slower.