Weather Lab

Part I

Purpose:

To become more familiar with different types of temperature scales and how to measure temperature itself. We were also taught about due point and relative humidity in this lab as well.

Background Information:

There are many various ways to measure temperature. One ways is by using a thermometer, which is a tool used to measure a temperature of system. However, there are many times of thermometers that one could use the most commonly used is the Mercury or alcohol thermometers. According to http://galileo.phys.virginia.edu/outreach/8thgradesol/ThermometersFrm.htm the thermometer has some very interesting facts;

“The most common thermometer utilizes a liquid, either mercury or alcohol. A glass bulb, filled with this liquid, is connected to a glass capillary tube. When heated, the liquid expands from the bulb into the capillary tube, so that the change in temperature corresponds with the change in height of the liquid. Mercury is commonly used because there is a wide temperature range at which it is liquid: from -38.9 C to 356.7C.

More recently, alcohol thermometers have supplanted the use of mercury thermometers in schools because of dangers associated with mercury. If you use a mercury thermometer in the experiment, be especially careful that it does not break.

There are other, more complex types of thermometers as well. A Galileo thermometer applies the fact that liquids expand faster with increasing temperature than do solids. It is made of a column of fluid that contains solid spheres with a density close to that of the liquid. If the sphere's density is less than the liquid, it will float; if it is greater than the liquid, it will sink. As the temperature increases, the liquid will expand faster than the solid and the liquid's density will decrease at a quicker rate, so that the spheres will eventually sink. Each sphere in a Galileo thermometer is a specific density so that it will sink at an exact temperature, thus displaying the temperature of its surroundings. The photo at the left is of a Galileo thermometer, which are no longer commonly used.

A third type of thermometer, a bimetallic thermometer, is used in household applications such as the thermostat. This thermometer is made of two strips of different types of metal which are sandwiched together and rolled into a coil. The metals expand at different