Specific Heat Capacity
Temperature, Heat and Internal Energy · Specific Heat Capacity — Calculations and Calorimetry · Heat Capacity and Thermal Equilibrium
IB Physics SL topic guide
The Particulate Nature of Matter
The Particulate Nature of Matter is a core part of IB Physics SL. This guide connects the syllabus ideas behind Specific Heat Capacity, Latent Heat, Heat Transfer Mechanisms, The Greenhouse Effect, Climate Feedbacks and Equilibrium Temperature and 4 more units, shows how they appear in worked problems, and points you to the formulas and full lessons needed for exam revision.
What you will learn
The Particulate Nature of Matter syllabus outline
The units below follow the structure used in the full Study to Learn course. Use the outline to identify exactly which idea needs attention, then work through the public example before continuing to the complete lesson path.
Latent Heat
Phase Changes and Latent Heat · Heating Curves and Multi-Stage Problems
Heat Transfer Mechanisms
Conduction, Convection and Thermal Radiation · Blackbody Radiation — Stefan–Boltzmann and Wien's Laws
The Greenhouse Effect
The Greenhouse Effect · Modelling the Greenhouse Effect
Climate Feedbacks and Equilibrium Temperature
Modelling Earth's Equilibrium Temperature · Climate Feedback Loops
Ideal Gas Laws
Ideal Gas Laws · Units and Absolute Quantities
Kinetic Theory of Gases
Kinetic Theory · Maxwell-Boltzmann Distribution and Degrees of Freedom
DC Circuits
Current, Resistance and EMF · Series and Parallel Circuits · Potential Dividers and Sensors
Capacitors
Capacitance and Energy Storage · RC Circuits and Charging/Discharging
Free worked preview
Temperature, Heat and Internal Energy
This complete preview comes from the Specific Heat Capacity unit. It introduces the core language, shows the method in context, and gives you a real example of the lesson quality before you create an account.
Temperature, Heat and Internal Energy
Thermal physics begins not with equations but with careful definitions. The distinction between temperature, heat, and internal energy is one of the most commonly tested concepts in IB exams, precisely because students conflate them — a hot cup of tea and a lukewarm swimming pool make the point: the pool is cooler but holds far more internal energy. This vocabulary carries through specific heat capacity, latent heat, the gas laws, and thermodynamics.
Reading the Notation
You'll see a triangle Δ (capital Greek "delta") in front of many physics quantities throughout this course — it always means "change in", i.e. (final value − initial value). So ΔT means "change in temperature" = Tfinal − Tinitial, not "delta times T".
Small letters written after a symbol and slightly below the line (like the f in cf) are subscripts — they just label which version of a quantity you mean (e.g. cice = specific heat capacity of ice specifically, as opposed to cwater). They are not multiplied or exponents — they're just labels.
Small letters written after a symbol and slightly below the line (like the f in cf) are subscripts — they just label which version of a quantity you mean (e.g. cice = specific heat capacity of ice specifically, as opposed to cwater). They are not multiplied or exponents — they're just labels.
Three related but distinct ideas describe thermal physics:
| Quantity | Symbol | Meaning |
|---|---|---|
| Temperature | T | A measure of the average random kinetic energy of the particles in a substance. It determines the direction heat will flow (always hot → cold). |
| Heat / thermal energy | Q | Energy that is transferred between a system and its surroundings because of a temperature difference. |
| Internal energy | U | The total energy stored inside a system: the sum of the random kinetic energies and the potential energies of all its particles. |
Converting Between Temperature Scales
where
temperature measured in kelvin (the SI unit — always use this in equations)
temperature measured in degrees Celsius
A change of 1°C is identical in size to a change of 1 K — only the zero point differs (0 K = absolute zero = −273.15°C). So ΔT is the same number whether you work in °C or K.
Worked Example — Same Temperature, Different Internal Energy
A cup of tea (0.25 kg) and a swimming pool (50 000 kg) are both at 37°C.
Convert 37°C to kelvin: T(K) = 37 + 273.15 = 310.15 K — identical for both, since temperature only measures average particle kinetic energy.
But internal energy is the total energy of all particles combined, so it scales with mass. The pool has 50 000 / 0.25 = 200 000 times more mass than the tea, so (very roughly, ignoring differences in specific heat capacity due to dissolved substances) it stores about 200 000× more internal energy — despite both being at exactly the same temperature. This is why the pool takes so much longer to warm up or cool down than the cup.
Convert 37°C to kelvin: T(K) = 37 + 273.15 = 310.15 K — identical for both, since temperature only measures average particle kinetic energy.
But internal energy is the total energy of all particles combined, so it scales with mass. The pool has 50 000 / 0.25 = 200 000 times more mass than the tea, so (very roughly, ignoring differences in specific heat capacity due to dissolved substances) it stores about 200 000× more internal energy — despite both being at exactly the same temperature. This is why the pool takes so much longer to warm up or cool down than the cup.
Common MisconceptionTemperature is not the same thing as heat or internal energy. A cup of tea and a swimming pool can be at the same temperature, but the pool has vastly more internal energy because it has far more particles.
Reviewed by the Study to Learn editorial team · Updated 2026-07-24