Physics Heat Chapter Quiz

Differences Between Clinical and Laboratory Thermometer

• A clinical thermometer measures body temperature, while a laboratory thermometer is used for various liquid temperatures.
• Clinical thermometers typically have a limited range (35°C to 42°C), while laboratory thermometers can measure from -10°C to 110°C.
• Clinical thermometers often contain a kink to prevent mercury from retreating, whereas laboratory thermometers do not have this feature.

Mercury in Thermometers

• Mercury expands uniformly with temperature, providing accurate readings.
• Its high density allows for a slender thread that makes it easily readable on the scale.
• Mercury does not wet glass, ensuring a clear separation of temperature readings.

Kink in Thermometers

• A kink is a constriction in the glass tube of a clinical thermometer.
• It keeps the mercury in place after the temperature is measured, preventing it from falling back down.

Distinction Between Heat and Temperature

• Heat is the total energy of molecular motion within an object, while temperature measures the average kinetic energy of those molecules.
• Heat is measured in joules or calories, whereas temperature is measured in degrees Celsius, Fahrenheit, or Kelvin.

Conduction, Convection, and Radiation

• Conduction involves direct contact between materials transferring heat (e.g., metals).
• Convection occurs in fluids (liquids and gases) where warmer areas rise and cooler areas sink, creating a current.
• Radiation transfers heat via electromagnetic waves without needing a medium (e.g., sunlight).

Wearing Light-Colored Clothes in Summer

• Light-colored clothing reflects sunlight, reducing heat absorption compared to dark colors which trap heat.

Importance of Washing Clinical Thermometers

• Washing before and after use ensures hygienic handling and prevents cross-contamination of bacteria.

Heating Metal Ball by Convection

• A metal ball cannot heat effectively through convection since it does not conduct heat efficiently in air, which lacks direct contact with a heating medium.

Covering Ice Slabs with Gunny Bags

• Gunny bags insulate ice slabs, slowing melting by reducing heat transfer from the environment.

Acid Storage

• Acids, such as hydrochloric acid (HCl) and sulfuric acid (H2SO4), should not be stored in metallic containers as they can corrode and react with metals, compromising safety.

Neutralization and Its Equation

• Neutralization is the reaction between an acid and a base producing salt and water, typically written as:
  • Acid + Base → Salt + Water.

Glass Containers

• Glass containers are preferred for storing acids because they are resistant to corrosion and do not react with acidic solutions.

Outcome of Neutralization

• The reaction between an acid and a base during neutralization typically results in the formation of salt and water, minimizing the potentially hazardous properties of the reactants.

Test your knowledge on heat concepts with this quiz covering the differences between clinical and laboratory thermometers, the properties of mercury, and modes of heat transfer such as conduction, convection, and radiation. Additionally, explore practical applications like clothing choices in summer and proper thermometer usage.