🌡️ Temperature and Its Measurement 🔥❄️
👩⚕️ Meet Lambok and Phiban from Shillong! When Lambok felt feverish, his sister used a thermometer to check his temperature. But how do we really measure how hot or cold something is?
🔥❄️ 7.1 Hot or Cold?
🖐️ Activity: The Touch Test
Try this experiment with 3 water containers:
1 Put your right hand in warm water (A)
2 Put your left hand in ice water (C) for 2 minutes
3 Now put both hands in room temperature water (B)
🤯 Surprise! The same water feels warm to one hand and cool to the other!
Our sense of touch can’t always be trusted to measure temperature accurately.
🌡️ 7.2 What is Temperature?
Temperature = A reliable measure of how hot or cold something is
We measure it using a thermometer 📊
🏥 7.3 Types of Thermometers
👩⚕️ Clinical Thermometer
- Measures body temperature
- Normal body temp: 37°C (98.6°F)
- Digital versions are safest
- Range: 35°C to 42°C
⚠️ Safety Tip: Always clean the tip before and after use!
🔬 Laboratory Thermometer
- Used for science experiments
- Typical range: -10°C to 110°C
- Contains alcohol (red) or mercury
- Measures in 1°C divisions
✅ Correct Way to Use:
- Don’t let bulb touch container sides
- Hold vertically
- Read while still in liquid
- Eye level with liquid column
🌤️ 7.4 Measuring Air Temperature
Weather reports show:
- 🌞 Maximum daily temperature
- 🌜 Minimum daily temperature
Did you know? Anna Mani, the “Weather Woman of India”, invented many weather instruments!
🌍 Temperature Scales
| Scale | Unit | Symbol | Example |
|---|---|---|---|
| Celsius | degree Celsius | °C | 37°C (body temp) |
| Fahrenheit | degree Fahrenheit | °F | 98.6°F (body temp) |
| Kelvin | kelvin | K | 310K (body temp) |
Conversion: K = °C + 273.15
📝 Summary
- 🌡️ Temperature measures hotness/coldness
- 🏥 Clinical thermometers measure body temp (35-42°C)
- 🔬 Lab thermometers have wider range (-10-110°C)
- 🌤️ Weather reports show max/min air temperatures
- 📊 Three scales: Celsius (°C), Fahrenheit (°F), Kelvin (K)
🔍 Fun Activities
🕵️ Temperature Detective
Track your body temperature at different times of day
🌦️ Weather Watcher
Record daily max/min temps from weather reports
🌡️ Thermometer Challenge
Practice reading different thermometer scales
🌡️ Class 6 Science Chapter 7: Heat – Questions and Answers
📷 Image-Based Question: Thermometer Reading Practice
Q: Who do you think followed the correct way for measuring temperature?
- Student 1: Touching the glass – ❌ Incorrect
- Student 2: Held vertically, bulb fully immersed without touching walls – ✅ Correct
- Student 3: Not immersed enough – ❌ Incorrect
- Student 4: Touching the container – ❌ Incorrect
✅ Correct Answer: Student 2
🧠 Objective Questions
- Normal temperature of a healthy human being is:
Answer: (ii) 37.0 °C - 37 °C is equal to:
Answer: (iv) 98.6 °F
✍️ Fill in the Blanks
- The hotness or coldness of a system is determined by its temperature.
- The temperature of ice-cold water can be measured using a thermometer (correction).
- The unit of temperature is degree Celsius.
📏 Thermometer Concept
- Type of thermometer shown: Laboratory thermometer
- Reading: As per image – mark the level of red column
- Smallest measurable value: Depends on scale. If 10 divisions per 1°C, then 0.1 °C
❌ Why not use Lab Thermometer for Body Temperature?
Lab thermometer has a wide range and cannot be placed in the mouth safely. Clinical thermometer is designed for human body temperature measurement.
📊 Vaishnavi’s Fever Table (Sample)
- Highest recorded temperature: 102.6 °F
- Day and time of highest temperature: Day 2, evening
- Day when temperature returned to normal: Day 3, morning
🔍 Identify Suitable Thermometer
Q: To measure 22.5 °C, use a thermometer with range including 22.5 °C and division size of 0.5 or 0.1 °C.
📈 Thermometer Reading – Fig. 7.10
Answer: (ii) 27.5 °C (if the red line ends halfway between 27 and 28)
🧮 50 Divisions Between 0 °C and 100 °C
Each division measures: 100 ÷ 50 = 2 °C
✏️ Draw Thermometer Scale (10 °C to 20 °C, 0.5 °C divisions)
Draw 20 equal divisions. Label every full °C (10, 11, 12, …, 20). Each tick = 0.5 °C.
💬 Komal says 101 degrees – Which scale?
Answer: Fahrenheit scale. (101 °C would be dangerously high; normal body temperature is ~98.6 °F)
🧪 Red Column Coloring Task (Fig. 7.7)
- Shade red column up to 7.5 °C, 14 °C, and 17 °C on three thermometers.
- Ensure equal spacing per 1 °C and proper labeling.
Tags: Class 6 Science Chapter 7 Heat, NCERT Solutions 2025–26, Body temperature, Thermometer reading, Temperature conversion, CBSE Class 6 Science Notes
