Heat Transfer Calculator (Q = m × c × ΔT)
The basic heat equation: energy needed to change the temperature of a material without changing its state.
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Formula
- Q = m × c × ΔT
Variables
- m
- — Mass
- c
- — Specific heat
- ΔT
- — Temperature change
Example calculation
Heating 100 kg of water (c = 4.186 kJ/kg·K) by 40 K takes 16,744 kJ ≈ 4.65 kWh.
Practical HVAC use
Size water heating, estimate tank recovery, or check how much energy a thermal mass stores.
Common mistakes
- Mixing kJ/kg·K with BTU/lb·°F.
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Educational tool. Results are estimates from the stated formulas; always confirm with manufacturer data and the code adopted in your jurisdiction. All calculators