Key relationship
Tf=(m₁c₁T₁+m₂c₂T₂)/(m₁c₁+m₂c₂); temperatures approach Tf conserving total energy.
Physics · Class 11
Bring two blocks into contact
Temperature describes thermal state; heat is energy transferred because temperatures differ. The isolated blocks approach a common temperature determined by their heat capacities. Equal masses do not guarantee a simple average unless their specific heats are also equal.
Open the interactive experiment →Bring two blocks into contact
வெப்பநிலை வேறுபாட்டால் வெப்ப ஆற்றல் பரிமாறும். சமநிலையில் இரு பொருட்களுக்கும் ஒரே வெப்பநிலை இருக்கும்.
Key notes, relationships and model limits
Remember
Temperature describes thermal state; heat is energy transferred because temperatures differ. The isolated blocks approach a common temperature determined by their heat capacities. Equal masses do not guarantee a simple average unless their specific heats are also equal.
Common trap
An object contains internal energy; heat names a transfer process.
Model limits
Two lumped blocks isolated from surroundings. A phenomenological exponential with 2 s relaxation time illustrates contact; heat capacities are constant and state changes are excluded.
What you will learn
Distinguish heat from temperature and conserve energy during equilibration.
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
Each block has heat capacity 1000 J/K. A cools by 30 K, transferring 30000 J to B, which warms by 30 K.
Why this matters
The model connects bring two blocks into contact with an observable reading. Check the equation and assumptions before applying it.
Before you start
SI units · algebra · graph reading
Check your understanding
Equal heat-capacity blocks start at 80°C and 20°C. What is final temperature?
- 80°C
- 50°C
- 20°C
Read the explanation
Equal capacities give the arithmetic mean (80+20)/2.
Course connection: Class XI Chapter 10. Consult the roadmap for CBSE, NEET, JEE Main and Advanced scope.