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Film summary
Microwaves are not only used to heat food. Cell phones utilize this type of electromagnetic radiation, allowing us to communicate over large distances.Key facts
- Cell phones work by converting sound into electrical signals, which can be transmitted as microwaves.
- Microwaves have a lower frequency than infrared and visible light, but shorter wavelengths and higher frequencies than radio waves.
- As high-frequency waves, microwaves can carry a lot of information - and their short wavelength means the transmitter, or cell phone handsets, can be small.
- Base stations around the world help microwaves to travel further.
Transcript
The invention of the telephone in the late 19th century was revolutionary.
It allowed sounds to be converted into electrical signals and transported through cables underground - a technique that still applies to your landline.
Rather than being confined by cables, cell phone conversations travel through the air, using microwaves.
When you …
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