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Radio, microwaves and infrared
Different parts of the electromagnetic spectrum have useful applications. Radio waves are used for television and radio broadcasting. Microwaves are used for satellite communications and for cooking food. Infrared is used in electrical heaters, for cooking food and in infrared cameras. An infrared camera makes a picture from infrared arriving from a scene; it can show temperature differences without relying on visible illumination. Learn both cooking examples: cooking is not limited to microwaves. In the diagram, each device is a familiar example of a use, rather than a drawing of the wave’s actual size.
