Physics

Heat Calculator

Calculate heat energy transfer (Q = mcΔT).

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THE NUMORIX GUIDE

How to use the Heat Calculator

Last reviewed September 14, 2026

What this calculator does

Sensible heat is calculated with Q = m c Delta T, where Delta T is final temperature minus initial temperature.

Formula and method

Sensible heat is calculated with Q = m c Delta T, where Delta T is final temperature minus initial temperature. The engine selects c from its material table and reports joules and kilojoules.

Variables and inputs

Mass m is in kg, specific heat c in J/(kg*K), and initial and final temperatures are entered in degrees C. The default is 1 kg of water, c = 4,186 J/(kg*K), heated from 20 C to 100 C; a custom option is listed in the selector.

Worked example

For 1 kg of water from 20 C to 100 C: Delta T = 80 K and Q = 1(4,186)(80) = 334,880 J = 334.88 kJ. A negative Delta T would produce a negative heat transfer, indicating energy leaves the material.

How to interpret the result

The result estimates energy transferred to or from a material when its temperature changes without a phase change. A positive Q means the material gains heat under the sign convention used here.

Common mistakes to avoid

Use the temperature difference, not the absolute Celsius readings, and keep mass in kilograms. Do not use this equation across melting or boiling without adding latent heat, and do not assume the listed c remains constant over a large temperature range.

Assumptions and limitations

The model assumes a uniform material with constant specific heat and no heat loss to the surroundings. Although the UI lists Custom, its current component never enables the custom-specific-heat field; selecting Custom therefore falls back to the water value 4,186 J/(kg*K).

Sources and references

COMMON QUESTIONS

Frequently asked questions

Why can Celsius be used with specific heat per kelvin?

Celsius and kelvin have the same size interval. Their different zero points cancel when calculating Delta T, so a change of 80 C is also 80 K.

Does the Custom material option accept my entered specific heat?

Not in the current UI. The selector displays Custom, but no code turns on the custom input, so the engine falls back to the water value instead of reading customSH.