Materials Required
  • A thermometer
  • A straw

How to do it

  • Take a straw and Blow through the straw.
  • Feel the air coming out through the straw.
  • Are you sure it is cool. Check it out.
  • Take a thermometer. shake well to bring the level of the mercury down.
  • Now let us begin with the experiment.
  • Blow through the straw on the bulb containing the mercury will rise.

Explanation

  • When the air is blown from our mouth, it enters the straw which contracts the air. The contraction makes the air warer.