What happens when an Object is Heated? Give an Equation for Energy Transferred | -This has the Energy being Transferred to the Thermal Energy Store of the Object, and the Temperature
Energy Transferred = Mass x Specific Heat Capacity x Temperature Change |
How can Heat Energy be Transferred? | -Conduction
-Convection
-Radiation |
What happens in Conduction? | -When the Object is Heated, the Particles get an Increase of its Thermal Energy Store
-This allows them to Vibrate even more, and having Collisions which Transferrers Their Kinetic Energy Store to the Neighbouring Particles Kinetic Energy Store
-This keeps Happening, until the Energy has been Spread Out Evenly, and the Objects Temperature is the Same Everywhere
-This can happen mainly in Solids, as the Particles are Next to Each other. |
What is Thermal Conductivity? What's Metals and Liquids Conductivity? | -This simply Describes how well an Object can Transfer Energy via Conduction
-Metal has a High Thermal Conductivity
-Liquids do Not have a High Conductivity [Low] |
What happens in Convection? | -When a Liquid or a Gas is Heated up, the Particles moves Faster and becomes Less Dense
-Warmer Less Dense Fluid rises Up, past the Colder Denser Surroundings
-This makes the Cooler Fluid fill up the Place that the Hot Fluid once was in, allowing it to all Repeat
-This is a Convection Current
-Keep in mind, the Warmer Particles will take their Kinetic Energy Store, and have it be Taken up |
How can you Reduce Convection? | -Simply making the Fluid stop Moving will reduce the Convection
-Clothes, Blankets and Foam Cavity Wall Insulation will work as it Traps Pockets of Air.
-Air not being able to Move means the Conduction will slow Down |
What happens in Radiation? | -Radiation, unlike Convection and Conduction, doesn't require any Particles so it can travel through Radiation
-This Energy can be Transferred as Infra-Red Waves [And they can be Detected using a CT Scan] |
-In terms of Absorption and Emitting, what happens if the Object is:
-Cooler Object next to a Hotter Object
-Matt Black Surfaces
-Light-Coloured, Smooth and Shiny Objects | -If a Hot Object is near a Cool Object, then the Thermal Energy Store of the Hot Object will Transfer some Energy via Infra Red to the Cool Object's Thermal Energy Store
-Matt Black are very good Absorbers and Emitters
-Light-Coloured, Smooth and Shiny Objects are Bad Absorbers and Emitters |