Experiment: What floats in the Dead Sea?

You have probably seen the picture of people floating on their backs in the Dead Sea, reading a newspaper or a book. But do you know why they are floating?

You need:

  • 2 large plastic containers
  • Water and a lot of salt
  • Different kinds of vegetables and fruits (or other things you might want to experiment with)

Mix a lot of salt with the water (salt dissolves more easily if the water is warm!) in one of the plastic containers to represent the Dead Sea, and fill the second container with tub water at the same temperature as your “Dead Sea”. In the Dead Sea, the salinity is 33,7%, that means to reproduce that you need ca 1 kg salt for 4 liters of water!

Now look at all your fruits and vegetables. Which, do you think, will float in the “Dead Sea”? Which will sink? Does your answer change if you look at your second container with tub water?

Flyter kokosnøtten? Fra Forskningsdagene i Bergen. Foto: UNI research

Does the coconut float? Fra Forskningsdagene i Bergen. Foto: UNI research