Английский язык. Ч.3 (Units 9,10). Ильичева Н.А - 20 стр.

phase, destructive interference occurs, which means the light is transmitted at
the bottom of the film surface rather than reflected. Because the film thickness
varies, a colourful display is seen for the different wavelengths of light.


C. On a hot day, there can be a layer of very hot air next to the roadway (made
hot by the Sun beating on the road). Hot air is less dense than cooler air, so the
index of refraction is slightly lower in the hot air. In the picture we see a
diagram of light coming from one point on a distant car (on the right) heading
left toward the observer. Wave fronts and two rays are shown. Ray A heads
directly at the observer and follows a straight-line path representing the normal
view of the car. Ray B is a ray initially directed slightly downward. But it does
not hit the ground. Instead, ray B is bent slightly as it moves through layers of
air of different index of refraction. The wave fronts move slightly faster in the
layers of air nearer the ground. Thus ray B is bent as shown and seems to the
observer to be coming from below (dashed line) as if reflected off the road.
Hence the mirage.


D. Because the path of light traveling from the bather’s foot to the observer’s
eye bends at the water’s surface, and our brain interprets the light as having
traveled in a straight line, from higher up (dashed line).




17. a) What work was Albert Einstein awarded a Nobel Prise for in 1921:
      1. the development of a mathematical theory of Brownian motion, 2. his
      paper on ‘Special Theory of Relativity’, 3. the paper in which he
      explained the photoelectric effect by means of Planck’s quantum theory?




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