Quick Notes

Quick Notes

Science Chapter 9: Heat
9.3 Principle of Expansion and Contraction of Matter 
9.3  Principle of Expansion and Contraction of Matter  
   

Expansion and Contraction of Matter

  • Heat can cause solid, liquid and gas to expand and contract
   
Solid Liquid & Gas

 * Particles in solid vibrate at a fixed position

  *  Particles in liquid & gas  vibrate at a fixed position
 * When the solid is heated, the particles vibrate faster and move further apart from one another which cause the solid to expand  * When the liquid and gas are heated, the particles move faster and randomly. This cause the distance between particles to increase and th eliquid and gas expands 
 * When the solid is cooled, th eparticles vibrate slower and move closer to one another which cause the solid to contract  * When the liquid and gas are cooled, th eparticles move slower and closer to one another which cause the liquid and gas to contract

The uses of expansion and contraction of matter in daily life

  1. Mercury in a thermometer is a heat conductor that can expand and contract
  2. Steel bridges are built with rollers and a gap on one end. This allows the bridges to expand in hot weather