Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
On a showery afternoon the Sun is above the horizon, and you see two rainbows.
In each raindrop sunlight is refracted, reflected once at the back, and refracted again. Red comes back at about from the point opposite the Sun, violet at about , so red is on the outside. The point opposite the Sun is as far below the horizon as the Sun is above it. A fainter second bow, at about , has two reflections and its colours reversed.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. (a) above the horizon.
Step 2. (b) above the horizon.
Step 3. (c) The main bow has red on the outside, so red is on top. The second bow, with two reflections, has the colours reversed: violet is on top.
Answer: (a) . (b) . (c) red for the main bow, violet for the second.
Log in to join the discussion.
Loading…