Fill in the gaps using the notes pages and own knowledge: All types of electromagnetic waves travel at the same s________ through a vacuum. The seven different groups of electromagnetic radiation have different properties because they have different w_____________. Different wavelengths of electromagnetic radiation are reflected, a___________ and transmitted differently by different substances and types of surface. When an object absorbs electromagnetic radiation is has one of two effects: h_____ it up or produces an a________ current. Some types of EM cause damage to cells which leads to cancer, others have few dangers. The shorter the wavelength the more d__________ than EM with longer wavelengths. List the main hazards of each high frequency EM and come up with some ways people could protect themselves from them:

Fill in the gaps: Communication signals can be a__________ or d__________. The following diagrams are what type of signal â&#x20AC;&#x201C; analogue or digital: _____________ _____________ _____________ Which type of signal loses more quality as they are transmitted : ______________ Complete the following calculations using the wave formula: Wave speed (metres/sec) = frequency (hertz) x wavelength (metres)

Ar trian range in gle if you l i ke

1) If frequency is 200 Hz and the wavelength is 20 m what is the wave speed? _______ 2) If frequency is 4000 Hz and the wavelength is 1000m what is the wave speed? ____________

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