Total internal reflection
In the “static apnea” discipline in freediving, many cool pictures of athletes are taken underwater in a way that plays with the reflection of the athlete in the still water…
Tag: refraction
Sunday #wavewatching. Shallow water waves, deep water waves, #wakewatching, reflections, refractions, and more.
This is the blogpost I wanted to write today before I got distracted by all the adventures on MS Stadt Kiel with sightseeing and swing dancing and all the good stuff…
The wonders of a Wadden Sea. Or what someone addicted to #wavewatching thinks they are
As someone living on the German Baltic Sea coast, I don’t spend a lot of time on the North Sea coast (except, actually, my week-long vacation after Easter with my…
Influence of wind and water depth on a wave field (or: a beach vacation in Dornumersiel)
I took the selfie above mainly to send to my mom from my vacation in Dornumersiel on the German North Sea coast. But then when looking through the hundreds of…
Reflecting waves, reflected and refracted light, and a Fata Morgana
How much physics can you spot in a single picture? What I see here: Waves and their reflection on the sea wall (Do you see the two main fields? One…
Guest post: Alice shows magic tricks and explains refraction of light in water
My friend Alice Langhans runs a super cool science communication Instagram (@edu_al_ice), where she posts about her experiences as PhD student in physics education research. And there is a lot more…
The first autumn storm and its impact on dye tracer and water level
Last night it rained a lot. So the first thing to do this morning was to check what that had done to my green lake! The dye is now a…
Wave watching: Refraction and diffraction of waves
A little more wave watching, today with a focus on how waves change direction when they run into shallow water. Let’s look at this beautiful wave and see what happens when…
Weekend wave-watching
Of course I did not only take pictures of lighthouses and instructional activities during the teacher training at Lotseninsel last week. I also took TONS of pictures of water! Some…
Refraction of waves towards the beach
As you see from my parents’ attire and the lack of leaves on the trees, these pictures are not brand new. But still interesting: Do you see how the waves…
Refraction of light in moving water — why stuff seems to be jumping around
I was waking along Kiel fjord one morning and noticed a stone “jump” on the ground as waves went over it (and actually, that observation was the motivation to dive…
Refraction of light in water — looking at a couple of examples
Looking at how light gets refracted when it enters water is always fascinating. There are a dozen blog posts on the topic on this blog alone, but let me talk…
Bubbles and the sun
One thing that I always notice but that is really difficult to take pictures of: How bubbles on a water surface focus the light into little stars on the ground.…
Another wave hunt expedition: Learning to discover ocean physics wherever you go
One of my favourite topics right now: Learning to “see” ocean physics wherever you go. For example here: A visit to my goddaughter in Schleswig, and this time we are practicing all…
Looking at how waves are bent
As soon as waves run into water that becomes shallow enough for the wave to “feel” it, the waves start changing how fast they propagate. And depending on the shape…
Wave hunt expedition. You don’t need to live close to the coast to observe all kinds of wave phenomena!
A 1.5 hour walk around a lake — and 242 photos of said lake — later I can tell you one thing: You definitely don’t need to live close to…
The difference between secondary rainbows and double rainbows
More reflection or more rain? Ha, aren’t you enjoying talking about optics again? Sometimes you see two rainbows that both have red on the outside and blue on the inside.…
Sun dogs
Recently spotted: sun dogs, a special form of halo! Or rather sun dog (singular), since there was only one to be seen and not a second one at equal distance…
Refraction of waves
I remember being on a looooong walk on some Danish dike when my sister was small and really didn’t want to walk any more, telling her about how phase velocity of…
Eddy generation and optics.
Eddies. Dips in the surface and shadows on the ground. I always get really fascinated by watching how eddies are generated by obstacles in a fluid. But it is especially…
Sun dogs
More refraction of light. Recently I found myself on the ferry from Kiel to Gothenburg, watching the sun rise. Next to the sun, I noticed a piece of a rainbow.…
What are the ingredients of a rainbow?
Still collecting materials for our instructional short movies. A while back I talked about how my colleague and I were experimenting with short instructional screen casts, and I shared some…
Why do we only see rainbows in the mornings and evenings, but never at noon?
Another movie on rainbows My dearest readers, I hope you are still as fascinated by rainbows as I am? Today I’m giving you another movie explaining something rainbow-related, namely why…
Rainbows III
Updated movie following Arne’s advice. When I asked for feedback on the rainbow movies the other day, Arne had a pretty good idea for how one of the explanations could…
Secondary rainbows
Sometimes you get lucky and see a double rainbow. But how does the second rainbow form? On my first 17th of May in Bergen, Ellen invited me to her home…
Rainbows and refraction II
Taking the same graphics as in this post, but presenting them differently. In the previous post, I presented a screen cast explaining, in a very text-booky way, how rainbows form.…
Rainbows and refraction
Why is a rainbow always red on top and blue at the bottom? We always talk about prisms and refraction and stuff, but be honest – would you be able to…
Sun halo
A rainbow that isn’t one, technically speaking. Browsing through the photos on my phone, I came across the one below that I took two years ago in Bergen. I remember taking…
Refraction of light in water – sticks and lenses.
Deformation in the water surface focussing light. Talking about how a deformation in the surface leads to light being focussed in different ways here and here, another example came to…
Eddies – surface imprint and optical properties
You can see “shadows” of eddies on the ground! As everybody who has ever watched a bath tub drain knows – eddies do lead to a deformation of the water’s surface.…
Refraction of light in water – coins and lenses.
More on what water can do to light. Remember my fascination with dandelions? Just to remind you: Especially in combination with coins and water droplets, dandelions are a source of…
Refraction of light in water.
What water can do to light. In the last post, I showed you a couple of pictures of a vase filled with dandelions. Turns out this might not have been enough of…
The broken spoon
Refraction of light in water. I just happened to notice this the other day, so I thought I’d take a picture and share it with you. It is amazing how…