conduction,convection,radiation(energy transfer) Flashcards
name the 3 ways thermal energy can be transferred
-conduction
-convection
-radiation
define conduction
when particles collide into others when they vibrate.
in what state does conduction happen
in solids
why are non metals such as wood, bad conductors
they are insulators. although some energy is being transferred, it is very slow.
what are conductors
the materials or substances which allow electricity to flow through them
what are insulators
a material which does not easily allow heat and/or electricity to pass through it.
e.g. Plastic, wood, rubber and glass
define convection
the movement of particles through a substance, transporting their heat energy from hotter areas to cooler areas in a circular motion
in what state does convection occur
in liquids and gases
what is infrared radiation
Infrared radiation transfers energy without particles – it is a wave.
what is infrared radiation also called
“thermal radiation” or “heat”
name the 2 main radiation from the sun
-infrared
-light
True or False
only the sun emits radiation
FALSE
ALL objects emit (give out) radiation
pick the right word:
Dark colours reflect/absorb infrared.
Light coloured and shiny surfaces reflect/absorb infrared.
Dark colours absorb infrared.
Light coloured and shiny surfaces reflect infrared.
what are some comparisons to conduction, convection and radiation
-you need particles to transfer energy by conduction or convection
-radiation can transfer through a vacuum and gases
-different types of radiation travel through different solids e.g. infrared can travel through a black plastic, but light can not.
what is the work equation for getting work done
Work done (J) = force (N) × distance (m)
