Electromagnetic Waves Flashcards
Do all electromagnetic waves travel at the same speed in a vacuum?
Yes
Which has the shortest wavelength and longest frequency?
Gamma rays
What has the longest wavelength and lowest frequency?
Radio waves
The higher the frequency of an electromagnetic wave…
The more energy it transfers
State the spectrum starting with the wave with the shortest wavelength and longest frequency?
Radio microwaves infrared light UV X-rays and gamma
What is the wave speed of electromagnetic waves when traveling through space?
300 million m/s
What are microwaves used in?
Communications. Microwave transmitters produce wavelengths that are able to pass through the atmosphere they are used to send signals to and from satellites and within mobile phone networks
What are radio waves?
Transmit radio and to programmes and carry mobile phone signals
Are microwaves and radio waves dangerous?
They will penetrate you skin and are absorbed by body tissue and can heat internal organs and damage them
Is infrared radiation dangerous?
It is absorbed by skin and can burn
The shorter the wavelength of the waves…
The more information they carry, the shorter their range, the less they spread out
What is a band?
The radio and microwave spectrum is divided into bands based on purpose
What do we know about the dangers of mobile phones?
Research is needed to evaluate their safety
What are microwaves used for?
Tv signals
What are optical fibres?
Very thin glass fibres. Used to transmit signals carried by visible light or infrared radiation. The signals travel down the fibre by repeated total internal reflection
