Waves Flashcards
What can we use Infrared for?
Remotes, thermal imaging, cooking
What can we use Radio waves for?
Television, Radio, Satellite transmission
What can we use Visible light for?
Seeing, Photos
What can we use Microwaves for?
Cooking, communication
What is the difference between L waves and T waves
With Transverse waves they vibrate perpendicular to the direction of travel, however with longitudinal waves, they vibrate parallel to the direction of travel.
How to transverse ways move
Oscillate perpendicular to direction of travel
What is frequency
Number of waves passing a certain point per second
What is wave length
distance covered by a full cycle of the wave, usually measured from peak to peak, or trough to trough
What are P waves
They are longitudinal waves that travel quickly through solids and liquids
What are S waves
They are transverse waves that can travel slowly through solids
What is reflection
When a wave hits boundary between two media where the wave speeds differ, but the wave stays in the original medium instead of passing into the second medium.
What is refraction
when a wave changes direction as it crosses a boundary.
Why does refraction occur
due to a change in the speed of the light ray or wave.
What is wave speed
the distance travelled by a wave per unit time, usually measured in metres per second (m/s)
What happens when the angle of incidence is less than the critical angle
Refraction
What happens when the angle of incidence is more than the critical angle
Reflection
What happens when the angle of incidence is equal than the critical angle
The line goes across the straight part of the semi circle
Why don’t we use radio waves for satellite transmissions
When radio stations use similar transmission frequencies the waves sometimes interfere with each other. Medium wavelength radio waves are reflected from the ionosphere so they can be used for long distance communication, but not for communicating with satellites above the ionosphere.
Uses for Ultrasound
Foetal scanning, cleaning jewlery, dog whisltle
Uses for infra sound
Detect meteors, elephant/whale communication, studying the earths strcuture
Where/How are gamma rays formed
Radio active decay
Where/How are VL UV and Xrays made
When electrons drop down energy levels
How are radio waves produced
Radio waves can be produced by oscillations in electrical circuits.
Do radio wave a long wave length
Yes, But a small frequency
Does Gamma rays have a long wave length
No, they have a small wave length and a large frequency
Why does light split up into different coulours
Different coulours have different wave lengths which means they travel at different speeds so they will refract by different amounts
