Optical fibres are constructed using transparent materials with different refractive indices.
Figure 14 shows one type of optical fibre that has a cylindrical core and surrounding cladding. Laser light of wavelength 565 nm is shone from air into the optical fibre (
- Calculate the frequency of the laser light before it enters the optical fibre. (1 mark)
--- 2 WORK AREA LINES (style=lined) ---
- Calculate the critical angle for the laser light at the cladding-core boundary. Show your working. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
- Calculate the speed of the laser light once it enters the core of the optical fibre. Give your answer correct to three significant figures. Show your working. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---