Question

How does the six's maximum and minimum thermometer help in measuring temperature accurately?

Answer 1

Six’s maximum and the minimum thermometer is mainly used for measuring the maximum and minimum temperature of the particular day.

Apparatus Description:

• The six’s thermometer consists of a U-shaped capillary tube with the bulbs at both ends
• The bend of the U shaped-tube is filled with mercury
• The composition of one of the bulbs is completely alcohol and the other bulb is partly filled with alcohol
• The tube which is partially filled with alcohol has a little space and is originally vacuum (does not contain alcohol vapour)
• The expansion and contraction of alcohol in the tube allow the change in temperature that has to be recorded
• Above the mercury, there are two dumbbell-shaped steel indices, that are kept in place by tiny steel springs
• The two dumbbell-shaped steel indices are used to reset to their initial positions. It is placed just above the mercury with the help of a horse-shoe magnet

Recording of the maximum temperature in the Six’s thermometer:

• The alcohol in the completely-filled bulb expands and exerts pressure on the mercury during the daytime as there is a rise in temperature
• The mercury in the bulb moves toward the partly-filled bulb and then pushes up the index in the capillary closer to the partly-filled bulb
• Hence, the index closer to the partly-filled bulb records the maximum temperature

Recording of the minimum temperature in the Six’s thermometer:

• The alcohol in the completely-filled bulb contracts due to the fall in temperature at night
• The mercury in the bulb moves toward the completely-filled bulb and pushes up the index in the capillary closer to the completely-filled bulb
• Hence, the index closer to the completely-filled bulb records the minimum temperature