6.1, 6.2 and 6.3 The Electromagnetic Spectrum/Light, Infrared, Microwaves and Radio Waves/Communications Flashcards
What do electromagnetic waves do?
Transfer energy from one place to another
What does the amount of energy that electromagnetic waves transfer depend on?
The wavelength of the waves
What is the order of the electromagnetic spectrum?
Radio waves Micro waves Infrared radiation Visible light Ultraviolet lights X Ray Gamma ray
How fast do all electromagnetic waves travel?
300 million m/s
Describe the similarities and differences of the EM waves
Similarities:
Same wave speed
All travel through a vacuum
Differences:
Different wave lengths
Different frequencies
How do we group the EM waves?
According to their wavelength
Which type of rays have the shortest wavelength?
Gamma rays
Which type of EM waves have the highest frequency?
Gamma rays
What is the average wavelength of a gamma ray?
10 to the power of -15 m
Or
0.000000000000001
(14 0’s)
Which type of EM waves have the longest wavelength?
Radio waves
What type of EM waves have the lowest frequency?
Radio waves
What is the average wave length of a radio wave?
10,000m
What is the relationship between the frequency of an EM wave and the amount of energy it transfers?
The higher the frequency, the more energy it transfers
Why are the wavelengths and frequencies at the boundaries of the different EM waves approximate?
The different parts of the spectrum are not precisely defined
How do different surfaces react to the different wavelengths of the EM waves?
Different wavelengths of EM radiation are reflected, absorbed or transmitted differently by different substances and types of surface
Which part of the EM spectrum transfers the most energy?
Gamma rays
What are electromagnetic waves?
Electric and magnetic disturbances
Where can we emit radio waves from?
An alternating voltage applied to an aerial emits radio waves with the same frequency as the alternating voltage. When the waves are received, they create an alternating current in the aerial with the same frequency as the radiation received
Name 3 uses of radio waves
- TV
- radio
- mobile phone
Name a danger of radio waves used in mobile phones
•radiation on the phone can cause damage to our brains