1. Open up your notes at page 9, note 15,Electromagnetic family – Names and Applications. Collect a highlighter or coloured pen. wavelengths diffracting TV Radio waves have longer wavelengths than TV, so radio waves diffract better than TV satellites Microwaves are one of the electromagnetic waves that can go up through the atmosphere around the earth without being reflected back to earth. They can also re-enter without any problems.

2. heat muscle dry thermal Police helicopters are fitted with thermal imaging cameras. This allows them to track people on the ground, even when they think they are hiding. Hospitals use thermographs to detect areas of infection or tumours. These areas are hotter than the rest of the body so show up as a different colour.

3. colours longer laser birthtattoos vaporise

4. Jump to note (5) on page 10 of the notes. sun heat burn cancer acne fluorescent security ultra-violet

5. black bones photographs slices 3

6. cancerous injected gamma blood tracer

7. Go back to page 10 of the notes. f = 2870 MHz = 2870 000 000 Hz v = 3 x 10 8 ms -1  = ? = v f = 3 x 10 8 2 870 000 000 = 0.1045296167247387 m TOO MANY SIG FIGS. SO 0.1 or 0. 105 m is acceptable

8. t = ? v = 3 x 10 8 ms -1 d = 980 km = 980 x 10 3 m t = d v = 980 x 10 3 3 x 10 8 = 0.0032666666666…. s HAS TOO MANY SIG. FIGS, SO…. 0.0033 s or 3.3 x 10 -3 s Problems, page 23 and 24. Then problems on pages 25 and 26.