User:0864867/Week 3

Quarter 9 is all about introductions about the topic Radiation and all of this information is found here.

Radiation

I did a research on understanding Radiation in forms of AM/FM and Hertz

You can read it here:

▪ WHAT ARE HERTZ?

Hertz is the amount of oscilation per second, it is the unit of frequency. The name comes from Heinrich Rudolf Hertz, he was the first one to provide proof of the existence of electromagnetic waves at around 1865. At around 1960 it was made official by the CGPM that frequency was now called Hertz. Before this frequency was expressed as ‘cycles per second’, such as ‘kilocycles’ & ‘megacycles’.

▪ AM / AMPLITUDE MODULATION In order to make sure you can send a message by radio, one has to modilate the signal. These modilations exists of different bandwiths which we can sense as different sounds in order to hear voices or music. Radio signals exists of a carrier, a standard wave which sounds monotone. This standard wave can be modulated in with to create a series of different sounds, in this way we can hear voices over far distance travelled by invisible waves in the sky. Amplitude in Dutch means: Omvang.

AM = Modulating the with of a wave

In the illustration above you can see how Hertz work. 1 Hz is 1 oscilation per second, 5 Hz is five oscilations per second, and so on.

Hertz has many multiples. Radiowaves are mostly expressed in kHz, MHz or GHz. 1000 Hz = 1 kHz 1000 kHz = 1 MHz 1000 MHz = 1 GHz Etc.

Radiations like long-wave infrared light is mostly defined by terahertz radiation. Higher frequencies like Gamma-rays is mostly measured in exahertz.