Följande problem kommer användas för de svenska uttagningarna för IPT 2018.

Problemformuleringen är på engelska för att inte förvränga betydelsen från den ursprungliga listan. Uppgifterna för den nationella uttagningen är ett urval av åtta uppgifter från listan för den internationella finalen. Den fullständiga listan hittar du här.

PDF med alla problemen.

För de svenska uttagningarna är de valda uppgiferna 1, 2, 3, 4, 5, 7, 9 och 13.

1. Sound thermometer     
Devise a method to obtain the temperature of a fluid by listening to the sound emitted when it is poured into a cup (see video). State the precision, accuracy and the limits of your method as well as the important parameters of the fluid.

2. Static speaker

Build an audio speaker without any moving part. Discuss the maximum bandwidth, signal-to-noise ratio and power efficiency achieved with your design. Is it possible to modify your device to use it as a microphone?

3. Ink tree

When a drop of ink is injected inside especially still water, or dropped very close to its surface, it firstly forms a ring of ink which then divides into smaller rings (see video). The process repeats again and again and forms a tree-like structure of ink. What is the maximal number of ring divisions that one can see and how does it depend on the important parameters?

4. Origami launcher

Folded paper structures such as the Miura-ori origami can be programmed to exhibit a wide range of elastic properties depending on their crease and defect patterns. Design and build an origami cannon to vertically launch a standard Ping-Pong ball using only a single uncut sheet of A4 paper (80g/m²). How is the height of the ball elevation related to the folding pattern? Optimize your design to achieve the maximum height possible.

5. Fluidic Calculator

Droplets having different concentrations of food coloring (containing propylene glycol) move in beautiful and intricate patterns when placed on a clear glass slide (see video). A wide variety of autonomous fluidic machines can be produced using this property. Implement diverse arithmetic operations using such droplets and optimize the operation speed.


7. Half-life sparkles

Sparks caused by an angle grinder tend to fly over a certain distance and then to split into several smaller sparks. What causes them to split? What is the condition for a split to occur? What influences the distance before the split? What will be the distance distribution of the sparks to fly?
Be extremely careful when performing experiments!

9. Screaming balloon

If you put a hex nut in a balloon it is possible to make it «scream» by giving a certain rotational movement to the balloon (see video). How do the characteristics of the sound produced depend on the important parameters of the system?

13. Egg white pearls

Egg whites are separated from the yolk and put into a syringe. From the syringe, the egg white is ejected into heated oil while the tip is in motion (see video). How does the size of the egg white pearls produced depend on the various parameters such as the temperature of the oil, ejection and motion speed, nozzle diameter or the non-Newtonian properties of egg whites?
Be extremely careful when performing experiments!