Temperature
🎯 In this topic you will
- Use instruments that measure temperature.
- Read and interpret the scales on a thermometer.
🧠 Key Words
- celsius (C)
- degree (°)
Show Definitions
- celsius (C): A temperature scale used in science where water freezes at 0°C and boils at 100°C under normal atmospheric pressure.
- degree (°): The unit used to measure temperature on a thermometer, showing how hot or cold something is.
🌡️ Hot, Cold, and Temperature
Everyone knows about hot and cold. We also need to know about temperature when we are cooking. Bake a chicken at 600°C and there would be no chicken left!
☕ Why Heat Matters
Putting a teabag into a mug of cold water would not work.
🧥 Temperature in Daily Life
If the temperature outside goes up or down, then you will need to change your clothes.
❓ EXERCISES
1. Read the scale. Write the temperature.
👀 Show answer
a. $28^\circ C$, $32^\circ C$, $12^\circ C$
b. $28^\circ C$, $32^\circ C$, $12^\circ C$
c. $28^\circ C$, $32^\circ C$, $12^\circ C$
2. Marianna reads the thermometer to the nearest division. Her answer is $20^\circ C$.
a. Is Marianna right? If she is not right, what should the answer be?
b. To the nearest marked division, the reading on this thermometer is $25^\circ C$, $30^\circ C$, $35^\circ C$.
c. Draw a red line to show a temperature of $27^\circ C$.
👀 Show answer
a. Marianna is not right. The correct reading is $15^\circ C$.
b. $30^\circ C$
c. Draw the line slightly above $25^\circ C$, close to $30^\circ C$.
3.
a. Which thermometers are labelled with divisions of $5^\circ C$?
b. What temperature does thermometer A show?
c. What temperature does thermometer B show?
d. Look at thermometers C and D. Which shows the higher temperature?
e. What temperatures do thermometers C and D show?
f. Draw your own thermometer to show a temperature of $26^\circ C$. Think about the scale that you will use.
👀 Show answer
a. Thermometers B, C, D and E.
b. $16^\circ C$
c. $16^\circ C$
d. Thermometer C.
e. C shows $15^\circ C$, D shows $14^\circ C$.
f. Any correct thermometer drawing showing $26^\circ C$ using a sensible scale.
🧠 Think like a Mathematician
Task: Design a poster that shows what you know about temperature.
Instructions:
- Use pictures, words and thermometers.
- Use the words degrees, Celsius and temperature.
Show Example Ideas
- Draw at least two thermometers with different red levels (for example $15^\circ C$ and $30^\circ C$).
- Label one picture “cold” and another “hot”.
- Write a sentence such as: “Temperature is measured in degrees Celsius ($^\circ C$).”
- Add everyday examples, like weather, tea cooling, or cooking.