P5.2 The Electromagnetic Spectrum Flashcards
How speeds of EM radiation differ in a vacuum and air
Electromagnetic waves all travel at same speed in a vacuum and in air
What type of waves can be produced by oscillations in an electrical circuit
Radio waves
How can radio waves create an alternating current in a circuit
When radio waves absorbed
they can induce oscillations in a circuit with the same frequency as the waves themselves
Where do gamma rays originate from
from changes in the nuclei of atoms
What type of spectrum do electromagnetic waves form
A continuous spectrum
What health effects can ultraviolet waves cause
cause skin to age prematurely
increase risk of developing skin cancer
What health effects can X-rays and Gamma rays cause
ionising radiation so can cause mutations in genes
lead to increased risk of developing various cancers
practical uses for infrared radiation
Electrical heaters
Cooking food
Infrared cameras
practical uses for microwave radiation
Satellite communications
Cooking food
Practical uses for radio waves
Television transmission
Radio transmission
Which part of the EM Spectrum can be seen by the human eye
Visible light
eye has a limited range of frequencies/wavelengths that it can detect.
What determines the colour of visible light waves?
The frequency of the light waves.
What colour of visible light has the highest frequency?
Blue
What colour of visible light has the largest wavelength?
Red
What technique is used to detect objects in deep water and measure water depth?
Echo sounding.
High frequency sound waves are emitted, reflected and detected.
Time difference between emission and detection, alongside wave speed, are used to calculate distances.
