Physics 4.11 - 4.14 Flashcards
What are the two types of microwaves
The two types of microwaves are those that can get absorbed by water and those that don’t get absorbed by water
Name some uses of both types of microwaves
Microwaves that get absorbed by water are used to heat food in microwaves because food has water which gets heated by the microwaves and those particles transfer energy to neighbouring particles which causes the food to heat up
Microwaves that dont get absorbed by water can be used for communication for example: overseas communication or satelite communication. The earth’s atmosphere contains water so in order to prevent the wave from being interupted by the water, we can use microwaves that don’t get absorbed by water
What is infrared radiation emitted by
It is emitted by objects that release thermal or heat energy
What is infrared radiation used for
It is used in cooking or heating up homes through heaters etc
True or false: The hotter the object the less infrared energy emitterd
False: The hotter an object is, the more infrared radiation it emits
What is fluoressence?
Fluoressence is when uv light is absorbed by particles which is them re emitted as visible light
Name 3 ways UV light can be used
Security
Sun tans
Sterilization of water
Name one way visible light is used
It is used in optical fibers or fiber optic cables
What can x rays be used for
Body scans
How are x ray images formed
Xrays are fired through an object and caught by a detector plate behind the object. The xray image starts off completely white and the areas that the object allows xrays to pass through turn black on the image and the areas that don’t allow xrays to pass through remain white or turn gray because a few xrays have passed through
What are gamma rays used for
They can be used for sterilizing equipment, curing food, treat cancer
What type of wave are sound waves
They are longitudinal waves
What is the average speed of sound waves
343 m/s
What mediums can sound travel through in order of best to worst?
Solid, liquid, gas
What mediums can’t sound travel through?
vacuums
