Thermometer

A thermometer is a tool used to measure temperature. It consists of a long, narrow, uniform glass tube with a bulb at one end. The bulb is usually filled with mercury or colored alcohol. As the temperature changes, the liquid expands or contracts, and the level of the liquid in the tube rises or falls. The temperature is then read from a scale marked on the tube.

Types of Thermometers

1. Mercury Thermometers: These thermometers use mercury as the liquid and are commonly used in households, hospitals, and laboratories.
2. Digital Thermometers: These thermometers use electronic sensors to measure temperature and display the reading digitally.
3. Infrared Thermometers: These thermometers measure temperature from a distance using infrared technology and are often used in industrial and medical applications.
4. Galileo Thermometers: These thermometers use the principle of buoyancy to measure temperature and are often used as decorative pieces.

How to Use a Thermometer

1. Hold the thermometer at the top end and gently shake it to bring the mercury or alcohol down to the bulb.
2. Place the bulb of the thermometer in the substance or environment whose temperature you want to measure.
3. Wait for a few minutes until the liquid stabilizes and then read the temperature from the scale.
4. After use, carefully dispose of the thermometer according to local regulations, especially in the case of mercury thermometers.

Study Guide Questions

1. What is a thermometer and how does it work?
2. What are the different types of thermometers and their uses?
3. Describe the steps involved in using a mercury thermometer.
4. How do digital thermometers differ from traditional mercury thermometers?
5. Why is it important to handle and dispose of mercury thermometers carefully?