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HEAT / THERMAL ENERGY. Phase Changes -Melting, Freezing, Evaporation, Boiling, Condensation, Sublimation. http://www.brainpop.com/science/energy/temperature/. Temperature:. the measure of the average kinetic energy of the particles in an object.
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Phase Changes -Melting, Freezing, Evaporation, Boiling, Condensation, Sublimation
http://www.brainpop.com/science/energy/temperature/ Temperature: the measure of the average kinetic energy of the particles in an object absolute zero: the temperature at which molecular motion stops.
Heat http://www.brainpop.com/science/energy/heat/ the energy transferred between objects that are at different temperatures Heat is always transferred from the object that has the higher temperature to the object that has the lower temperature
When matter is heated, the molecules react by….. -Speeding up -Spreading out This is known as thermal expansion -The increase in volume (size) due to added heat. Thermal: heat Expand: to get bigger When matter is cooled, the molecules react by….. -Slowing down -Contracting
Conduction Transfer of heat / energy through direct contact -Occurs best in solids
Conductors Insulators Wood Metal Objects Glass Water Cotton Rubber Air
Convection Transfer of heat / energy through liquids and gases -Involves circular currents based on density of cooler / warmer matter
Radiation Transfer of heat / energy through open space -Radiate: To Give Off
Light Energy radiated from the sun Only about half the energy from the sun reaches Earth. The other half is either reflected away or is absorbed by other factors
The Greenhouse Effect Warming that results when solar radiation is trapped by the atmosphere; caused by atmospheric gases that allow sunshine to pass through but absorb heat that is radiated back from the warmed surface of the earth
Brainpop greenhouse effect OZONE Ozone is a gas made up of three oxygen atoms (O3). It occurs naturally in small (trace) amounts in the upper atmosphere (the stratosphere). Ozone protects life on Earth from the Sun’s ultraviolet (UV) radiation. Pollution is depleting it – upsetting the natural balance of “good” ozone at the stratospheric level of the atmosphere