Technology 4 ESO – Unit 4 COMMUNICATION TECHNOLOGY page 54 activity 35
a) Watch the video on “Fiber optic cables” and answer:
- I) Why the light follows the liquid flow?
- II) What happens when a light ray his the surface at an angle greater than the critical angle?
- III) What is the basic property of the “cladding”?
- IV) How is the fibre made?
- V) How many optical fibres had the first fibre optic cable?
- VI) What are we doing when we alternatively block and not block the laser?
- VI) What is “pulse code modulation”?
b) In this link: https://en.wikipedia.org/wiki/Twisted_pair we can find information about the “twisted pair cable”.
Why twisting the paired cables together eliminates the external electromagnetic interferences?
