Specific heat capacity ($c$) is the energy needed to raise the temperature of 1 kg of a substance by 1 °C (or 1 K). The formula $Q = mc\Delta T$ appears in nearly every thermal physics paper.

Typical exam question: “A 2 kg aluminium block is heated from 20 °C to 50 °C. If $c$ of aluminium is 900 J/(kg·°C), calculate the energy transferred.”

Steps: 1) Identify mass, $c$, and temperature change. 2) Multiply: $Q = 2 \times 900 \times (50-20) = 2 \times 900 \times 30 = 54,000\, J$.

Key concept: Water has a high specific heat capacity, which is why it is used in cooling systems and why coastal climates are milder.

MYP frequently asks you to compare these three heat transfer methods (Criteria A: Knowing and understanding).

Conduction: transfer through solids (and to a small extent in fluids) by particle vibrations and free electrons. No overall movement of material.

Convection: transfer in fluids by bulk movement of the fluid itself (density changes).

Radiation: transfer by infrared electromagnetic waves; no medium needed.

Common application questions: vacuum flasks, solar water heaters, insulation in houses. For a vacuum flask, explain how each feature minimises heat transfer (silvered walls reduce radiation, vacuum stops conduction/convection, stopper reduces conduction/convection).