How Beautiful Rainbows Work (the science!)
We all love beautiful rainbows, that appear when it’s raining and sunny. But what are they, and how much do you know about them? Rainbows are simply a natural physics phenomenon, which happens when sunlight passes through raindrops, to act like tiny prisms, breaking the light into different hues.
Due to England having such changeable weather, we have more rainbows than most countries (they are common during short showers).
If sunlight bends and reflects light twice, you may see a double rainbow, the second one has its colours reversed. They are actually full circles, we only see the arc. Pilots in aeroplanes see the whole thing!
Rainbows only contain pure colours. So that’s why you’ll never see pink, as this is a mix of red (long wavelength) and blue/violet light (shorter wavelength).
Hawaii has the world’s most rainbows, as it has so much sun and rain!
We all know that a rainbow has seven colours, which always appear in the same order. This is because when light passes through water droplets, it bends and separates into wavelengths:
- Red has the longest wavelength and lowest frequency of visible light. So it bends the least.
- Orange is located directly beneath red, and bends slightly more, as it passes through watwer.
- Yellow is the upper-middle colour. As human eyes are sensitive to yellow light, it is one of the brighest bands in the sky.
- Green is the middle colour, and separates warmer longer wavelengths, from shorter cooler ones.
- Blue has a short wavelength, and scatters easily. The same reason why daytime sky appears blue.
- Indigo is a deep dark blue purple hue. This brings the spectrum to seven distinct notes, just like a musical scale.
- Violet is the innermost edge, this has the shortest wavelength. It bends at the sharpest angle, at the bottom of the arch.
Poetry break: The Rainbow by Christina Rossetti
Boats sail on the rivers,
And ships sail on the seas;
But clouds that sail across the sky
Are prettier far than these.There are bridges on the rivers,
As pretty as you please;
But the bow that bridges heaven,
And overtops the trees,
And builds a road from earth to sky,
Is prettier far than these.
Where are the Wettest Places in England?
Preston is England’s wettest cities, and nearly all the rainiest places are in the Lake District (England’s largest National Park). While in the south, the pavement can be dry in a few hours, here you can be soaked to the skin in a downpour, and it just rains and rains and rains!
It’s due to the Atlantic Ocean, which carries large amounts of moisture from the wind. Mountains (all of England’s highest ones are here) force air to rise. This causes ‘orographic lift. As air rises and cools, it can’t hold moisture, so water vapour then condensed into rain clouds – and lots of them!
How to Upright an Overturned Sheep
If you are out walking in the countryside, sometimes you may come across a sheep on its back. Sheep fall over either due to being heavily pregnant, or sometimes due to rain-soaked wool. Either way, it’s important to know how to quickly upright the creature, or else it will die.
Sheep stomachs ferment grass even when upside down, and this puts pressure on the lungs and heart. So they will die from suffocation or bloat, if nobody helps them get upright.
If there is no farmer nearby, here’s what to do:
- Approach the sheep from behind, brace against its back, grip the wool between the shoulder blades and lower back (never pull the wool) and gently roll the creature away from you, slowly tipping it upright.
- Hold the sheep upright on its rear legs to keep it steady for a minute, as it will have wobbly limbs, and blood circulation needs to normalise. Keep it secured to let excess rain drain off, to prevent the same happening again.
- Once the sheep can stand alone, let it return to its flock. Keep an eye on the sheep for a while, to ensure it’s okay. Inform the farmer if possible.
- Here’s a short simple video to show you what to do.
