Physics - Features of waves Flashcards
What do the oscillations look like in transverse waves?
The oscillations are at right angles to the direction of travel
What do the oscillations look like in longitudinal waves?
The oscillations are along the same direction as the direction of travel and energy transfer.
What are examples of transverse waves?
-all types of electromagnetic waves
-water waves
-seismic S waves
What are examples of longitudinal waves?
-sound waves
-seismic P waves
What is amplitude?
The distance from the rest and the top of the wave.
What is wavelength?
The distance from one point on a wave to the same point on the next wave. Easiest to measure from the crest.
What is frequency?
The number of cycles of a wave that occur in one second. The amount of humps on one side of the rest.
What is reflection?
When waves reflect off surfaces. Angle of incidence = Angle of reflection.
What is refraction?
Waves change speed when they pass across the boundary between two different substances, such as light waves refracting when they pass from air to glass. This causes them to change direction and this effect is called refraction.
Why does refraction happen?
Light travels slower in a more dense material like glass in oppose to air. The wavelength also decreases in order to keep the frequency constant. Wavelength is proportional to speed. Frequency doesn’t change.
What is the order of the electromagnetic spectrum form safest to most dangerous?
-Radio waves
-Microwaves
-Infrared
-Visible light
-Ultra violet
-X-rays
-Gamma rays
Red Monkeys In Vans Use X-ray Goggles.
What are the uses of all types of waves?
-Radio waves - Broadcasting and communication
-Microwaves - Cooking food
-Infrared - Night vision equipment
-Visible light - Human vision, photography
-Ultra violet - Fluorescent laps
-X-rays - Medical equipment
-Gamma rays - Sterilising food and medical equipment
What is the equation for wave speed?
v = f × λ
Wave speed = frequency x wavelength.
What is a geosynchronous satellite?
-Only above same point once every 24hrs. Can only communicate every 24hrs.
-Doesn’t rotate with earth.
What is a geostationary satellite?
-Always above the same point
-Rotates around equator
-Rotates with the earth.
