Science Projects And Inventions



  • A capped bottle
  • Water
  • A marker

Here is a riddle. A bottle which is capped seems to be half full of water. Given that the bottle has a long neck, it becomes difficult to gauge whether the water fills more than half the bottle, less than half or exactly half. How will you tell? Well here is how.

Mark the level of water on the outside of the bottle keeping the bottle in an upright position. Now turn the bottle upside down. If the water level is above the mark, the bottle is more than half full. If it is below the mark, it is less than half full. It is exactly half if the water level is right on the mark.


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