All questions of Temperature and its Measurement for Class 6 Exam

On the Kelvin scale, the boiling point of water is 373.15 K.

Understanding Water Boiling Point
Water boils at a specific temperature depending on the scale used to measure temperature. In the Celsius scale, water boils at 100°C.
Why Does Water Boil at 100°C?
- Boiling Point Definition: The boiling point of a liquid is the temperature at which it changes from a liquid to a gas. For water, this occurs when it reaches 100°C at standard atmospheric pressure (1 atmosphere or 101.3 kPa).
- Molecular Activity: At this temperature, water molecules have enough energy to overcome the forces holding them together in the liquid state. As they gain energy, they move faster and eventually break free to become steam (gas).
Comparison with Other Temperatures
- 0°C: This is the freezing point of water, where it changes from liquid to solid.
- 32°C: This is equivalent to 0°C in the Fahrenheit scale, not relevant for boiling.
- 273°C: This temperature is not standard for boiling water; it relates to absolute zero in Kelvin.
Conclusion
In summary, the correct answer to the question regarding the boiling point of water on the Celsius scale is 100°C. This is a fundamental concept in understanding phase changes in water, which is crucial for various scientific and practical applications.

Factors Influencing Body Temperature
Body temperature is a critical indicator of health, influenced by various factors. Understanding these factors helps in recognizing normal and abnormal temperature ranges.
Age
- Body temperature can vary with age. Infants typically have higher temperatures compared to adults, while older adults might have slightly lower temperatures.
Activity Level
- Physical activity raises body temperature as muscles generate heat. Exercise, especially vigorous activities, can cause a temporary increase in temperature.
Time of Day
- Body temperature fluctuates throughout the day, typically peaking in the late afternoon and declining during the night. This diurnal variation is part of our circadian rhythm.
Eye Color
- Eye color does not affect body temperature. Unlike the other factors mentioned, it is not a physiological characteristic related to thermoregulation.
Conclusion
- While age, activity level, and time of day are significant factors influencing body temperature, eye color is irrelevant in this context. Understanding these differences is essential for interpreting body temperature accurately.

Digital thermometers use electronic sensors to measure and display the temperature digitally.