Radiation Flashcards
What is radiation?
Radiation is the transfer of energy using waves.
What is a vaccum?
A vaccum is a space where there are no particles.
Radiation can occur in a vaccum
How can you see the levels of radiation emitted from objects?
What will you notice?
- Use an infrared (IR) camera
- More radiation emitted from hotter objects
What is the method for exploring which surface emitts more radiation, shiny silver or matt black?
1.) Boil the kettle to 100 degrees celcius
2.) Fill each beaker (matt black and shiny silver) with 200ml of water
3.) Position infrared thermometer 5cm from beaker 1 .
4.) Record temperature
5.) Repeat steps 3 and 4 for beaker 2
What is the independent variable in radiation experiment?
Type of beaker (matt black , shiny silver)
What is the dependent variable in radiation experiment?
Radiation emitted
* temperature on infrared thermometer*
What is the control variable in radiation experiment?
- Temperature of water
- Volume of water
- Distance between thermometer and beaker
What surface is the best emitter and absorber of radiation?
Black matt is the best emitter and absorber of radiation.
Why do people wear white clothes on sunny days?
White is a poor absorber of radiation.
The heat energy will be reflected slightly.
People can stay cool
Why are solar panels dark black?
Black is the best asborber of radiation
The heat energy can be absorbed to heat water in a boiler
Why is food wrapped in foil?
Shiny surfaces (eg. foil) are poor emitters
The thermal energy will be unable to escape from the food.
Keeps food nice and warm!
Why does a drink in a black mug cool faster than a drink in a silver mug?
- Black surfaces are good emitters and absorbers of radiation.
- This means it will emitt radiation to surroundings a lot quicker.
