Key relationship
T=Ta+(T₀−Ta)e⁻ᵏᵗ.
Physics · Practical apparatus
Cooling-curve thermometer
Take temperature readings at equal time intervals and observe a decreasing slope as the body approaches room temperature. Correct a thermometer zero offset before fitting.
Open the interactive experiment →Cooling-curve thermometer
வெப்பப் பொருள் அறை வெப்பத்தை அணுகும்போது குளிரும் வேகம் குறையும். பூஜ்யப் பிழையைச் சரிசெய்து வரைபடம் உருவாக்கவும்.
Key notes, relationships and model limits
Practical tip
Take temperature readings at equal time intervals and observe a decreasing slope as the body approaches room temperature. Correct a thermometer zero offset before fitting.
Common trap
The cooling rate decreases as the temperature difference from the surroundings decreases; it is not a constant slope.
Model limits
lumped Newton cooling at constant ambient and k, no phase change; time uses minutes.
What you will learn
Adjust cooling-curve thermometer apparatus, observe its reading and derive the indicated physical quantity.
Try the experiment
Try both scenarios, change one control, and predict the result before checking the graph and readouts.
Think of it this way
Change one input while keeping the others fixed, as you would in a controlled experiment.
Worked example
At T₀=80 °C, Ta=25 °C and k=0.1/min, after 10 min T≈45.23 °C.
Why this matters
The model connects cooling-curve thermometer with an observable reading. Check the equation and assumptions before applying it.
Before you start
SI units · algebra · graph reading
Check your understanding
As the object approaches ambient temperature, Newton cooling rate magnitude?
- Increases without limit.
- Decreases toward zero.
- Stays fixed until the object reaches ambient.
Read the explanation
Decreases toward zero.
Course connection: Virtual apparatus preparation. Check exact board/exam membership in the syllabus sources. Physical practical work remains necessary.