Thermometers

Definition

Thermometers are devices used to measure temperature by utilizing the physical properties of materials that change with temperature. They are crucial for accurate thermal measurements in various scientific applications.

5 Must Know Facts For Your Next Test

1. Mercury and alcohol thermometers operate based on the expansion and contraction of liquids.
2. Digital thermometers use electronic sensors to measure temperature changes, often providing more precise readings.
3. The Kelvin scale is commonly used in scientific contexts because it starts at absolute zero, the lowest possible temperature.
4. Thermocouples generate a voltage proportional to temperature difference between two different metals joined at one end.
5. Infrared thermometers measure the thermal radiation emitted by an object to determine its temperature without direct contact.

Review Questions

• What are the primary differences between mercury and digital thermometers?
• Why is the Kelvin scale preferred in scientific measurements over Celsius or Fahrenheit?
• How do thermocouples generate a voltage related to temperature?

Related terms

Temperature: A measure of the average kinetic energy of particles in a substance, indicating how hot or cold it is.

Absolute Zero: The theoretical lowest possible temperature where all molecular motion ceases, defined as 0 K or -273.15°C.

Thermal Expansion: The tendency of matter to change its shape, area, and volume in response to a change in temperature.