Waves Flashcards
What is a longitudinal wave?
When the vibrations are parallel to the direction of travel of the wave
What is a transverse wave?
When the vibrations are perpendicular to the direction of travel of the wave
Define amplitude
The maximum displacement from 0
What is wavelength?
The distance between two corresponding points on different waves/the distance between the start of two waves
What is time period?
The time taken for one complete wave to pass a point
What is frequency?
No. of waves passing a point in one second HZ
What do waves transfer?
Energy and information but not matter
What are radio waves used for?
Broadcasting and communication
What are microwaves used for?
Cooking and satellite communication
What is infrared used for?
Heaters and night vision
What is visible light used for?
Optical fibres and photography
What are ultraviolet rays used for?
Fluorescent lamps
What are x-rays used for?
Take a guess
What are gamma rays used for?
Sterilisation
List the electromagnetic spectrum in decreasing wavelength/increasing frequency
Radio Micro Infrared Visible Ultraviolet X Gamma
What damage do microwaves do?
Internal heating of body tissue
What damage do infrared rays do?
They burn the skin
What harm do ultraviolet waves do?
Damage surface cells and cause blindness
What damage do gamma rays do?
Cancer/mutation
What is the difference between analogue and digital?
- Analogue can take any value within a certain range
2. A digital signal only takes two values
Why is digital better than analogue?
- Both types need to be amplified
- They pick up interference along the way.
- Analogue amplifies the noise but digital doesn’t
