Hint for the preparation of the next experiments
24.12.2015: In case you might not have a transparent film, you can also print the two paages on A4 paper, place them on top of each other and hold them against a light source. This way you can also read the message.
23.12.2015: The "front edge" of the bowl is the one facing you during your observation. The "rear edge" is the one away from you.
19.12.2015: Rotation "in the direction of the black wings" means, that the wings rotate such that the black side moves forward in the rotation and the silver-white one points backwards. Or in other words: When watching the rotating wings moving towards you, you face the black side. Rotation "in the direction of the silver-white wings" means, that the wings rotate such that the silver-white side moves forward in the rotation and the black one points backward. When watching the rotating wings moving towards you. you face the silver-white side.
18.12.2015: In case you might not have a transparent film, you can also print the patterns on paper and hold them against some light source. Some of you apparently hold the coloured stripy pattern upside down. The might change the direction of rotation, but the object stays the same.
16.12.2015: "flat lentil shaped" means that the water drop is really flat, less than 1 mm high and runs out flat at its borders. "Rather spherical" means that the drop can also be more than 1 mm high and the border can be steeper. Try it out with a bit more water in the drop.
14.12.2015: Please note, that answer A) is not included in answer C). A) means that it is always exactly one configuration. C) means, depending on the location of the first candle, it can be 1, 2 or 3 configurations.
13.12.2015: Intead of a small slit, you can also poke a little hole into the black cardboard with a ball pen and shine through it with a torch or the mobile phone lamp. You can use a glass different from the one shown in the movie. However, it should have similar size and shape.
12.12.2015: It might be helpful to shine at the reflector from a distance of 1m or more so that you can see the effect more clearly.
07.12.2015: Today, you should move with stem of the glass at approximately 5 mm height over the paper. Directly on the paper is too close. The answers differ not only in the observation, but also in a possible explanation. Hence, only one is correct. Pay attention!
06.12.2015: In case you might not have a fine synthetic curtain at home, you might want to try silk tights. You can also look carefully at the fibre structure of the curtain in the movie, think a bit and exclude some options. In case you might only have a yellow Sodium lamp outside your window, you can still exclude some options with this.
11.11.2015: Here you can find a shopping list with material you need for "Physics in Advent - PiA2015".
By the way, you can find all "PiA - Physics in Advent" question and answer movies on http://www.youtube.de under "Physik im Advent" or "Physics in Advent". In case of any misunderstandings or ambiguities, we will post here additional hints for the experiment of the day. So it is worthwhile having a look here every day before you submit your answer. We wish you lots of fun with the experiments and best of luck in finding the answers!