Today we learn about heat.
Heat is used in daily life..There are 3 processes that are Conduction, Convectiion and Radiation.
* Conduction is the transfer of heat energy through a material to protect it from the hot to the cold regions without any visible movement or flow of the material.
* There are to substances in life that are the conductor and insulator...
- The insuulators are for example are water, glass, plastic or wood etc.
- The conductors are for examples are metal such as brass, steel,invar etc.
Convection is the transfer of heat from one part of the fluid to another by the circulating movement of the fluid itself. Radiation transfer heat in the form of electromagnetic waves and does not need a medium.
The meaning of the words is as shown below :
- CONVECTION - MOVING MOLECULES TRANSFER HEAT THROUGH LIQUID OR GAS
- CONDUCTION - HEAT MOVES THROUGH HOT SURFACE ONTO HOT TO COLD SURFACE
- RADIATION - TRANSFER HEAT IN THE FORM OF ELECTROMAGNETIC WAVES .
** TO REDUCE THE LOSS OR GAIN HEAT BY RADIATION , AN OBJECT SHOULD HAVE A SHINY, SILVERY OR/AND SMOOTH SURFACE TO HAVE AN INCREASE OF THE LOSS OR GAIN HEAT BY THE RADIATION AROUND THE SURROUNDING BY HAVING A DULL, BLACK AND HAVE A VERY ROUGH SURFACE.
CONVECTION GIVES RISE TO SEA AND LAND BREEZES. DURING THE DAY, THE LANDS HEAT UP FASTER AND REACHES A HIGHER TEMPERATURE MUCH MORE EASILY. THE AIR OVE R THE LAND GETS HEATED UP, EXPANDS AND WOULD BECOMES DENSER AND WOULD RISE. THE FLOW OF COOL AIR FROM THE SEA TOWARDS THE LAND THAT WOULD PRODUCE A SEA BREEZE.
THIS IS AN EXAMPLE OF A SEA BREEEZE..
A vacuum/ thermos flask keep things close to their original temperature by reducing the transfer of heat between the flask and its surrounding. Heat is obtained from various sources such as the SUN, burning fuels, and electrical heating appliances. Solar heaters are used to absorb heat from the Sun. It is also an easier way to save electricity !! 'o'
