Solve sensible heat transfer Q = m × c × ΔT, or solve explicitly for mass, specific heat capacity or signed temperature change. Choose energy units including J, kJ, thermochemical calories, Wh, International Table Btu and eV. This calculator does not model ideal-gas internal energy.
Thermal Energy Formula
The following constant-specific-heat relation describes sensible heat transfer for a temperature change without a phase change.
- Where Q is signed heat transfer (J): positive when heat is added to the material, negative when heat is removed
- m is the positive mass (kg when using SI units)
- c is the positive specific heat capacity (J/(kg·K) in SI), appropriate to the material, process and temperature range
- ΔT is the change in temperature
To calculate sensible heat transfer, multiply mass by specific heat capacity and by ΔT = final temperature minus initial temperature. A temperature drop gives negative Q; zero temperature change gives zero sensible heat. Select the desired solve mode rather than leaving an arbitrary field blank. For inverse mass or specific heat, Q = 0 and ΔT = 0 give no unique positive value, while nonzero Q with ΔT = 0 has no finite solution.
Thermal Energy Definition
Heat is energy transferred because of a temperature difference; it is not a substance containing energy. This calculator estimates a sensible-heat transfer using Q = m × c × ΔT, rather than the total internal energy stored in a system.
Thermal Energy Example
How to calculate thermal energy?
- First, determine the mass.
Measure the mass of the object, typically in units of kilograms.
- Next, determine the specific heat.
Use a specific heat appropriate to the material, process and temperature interval; the calculation treats it as constant and excludes phase changes.
- Next, determine the change in temperature.
Use final temperature minus initial temperature. Keep the sign: cooling gives a negative change. Temperature differences in °C and K have equal magnitude; a °F difference uses a factor of 5/9 with no offset.
- Finally, calculate the thermal energy.
Choose the quantity to solve for, enter the three visible source values and select Calculate. The answer appears separately and does not fill a fourth input.
FAQ
Thermal energy concerns microscopic contributions to a system’s internal energy. Heat transfer is energy crossing a boundary because of a temperature difference. The Q calculated here is a signed sensible-heat transfer under a constant-specific-heat model, not a calculation of all stored internal energy.
