Explain the working of ‘Six’s maximum and minimum thermometer’ with the help of a diagram.
- Six’s Maximum and Minimum thermometer is a U shaped parallel tube made up of glass. One side registers the maximum temperature and the other side records the minimum temperature.
- The bend at the bottom of the thermometer contains mercury which moves up or down based on the expansion and contraction of alcohol.
- When the temperature rises, the alcohol expands and pushes the mercury up the maximum column. This also pushes the mercury down in the minimum column.
- Similarly, when the temperature falls, the alcohol contracts and pulls the mercury up in the minimum column resulting in a fall of mercury in the maximum column.
- The steel indexes are located on the surface of mercury. They move along with the flow of mercury up and down.
- When the temperature reaches its maximum and minimum limits, the metal indexes remain at that place. This helps in recording the maximum and minimum temperatures of the day.