First Law of Thermodynamics Calculator
Solve for heat (Q), work (W), or change in internal energy (ΔU) using ΔU = Q - W
Calculator
Enter known values and leave the unknown blank. Units can be adjusted from the dropdown menus.
About the First Law of Thermodynamics Calculator
The First Law of Thermodynamics Calculator is a free online tool to solve for change in internal energy (ΔU), heat added (Q), or work done (W) in any thermodynamic process. Enter any two known values and leave the unknown blank to calculate it using the fundamental formula ΔU = Q - W.
What You Can Calculate
- Change in Internal Energy (ΔU): Energy variation within a system.
- Heat Added (Q): Thermal energy transferred to the system.
- Work Done (W): Mechanical energy transferred by or to the system.
Formulas Used in the Calculator
The calculator uses the first law of thermodynamics:
- ΔU = Q − W (Change in internal energy equals heat added minus work done)
- Q = ΔU + W (Heat added can be computed if ΔU and W are known)
- W = Q − ΔU (Work done can be computed if Q and ΔU are known)
How to Use the Calculator
- Enter any two known quantities (ΔU, Q, or W) and leave the unknown blank.
- Select the appropriate units (J or kJ).
- The calculator automatically computes the missing thermodynamic quantity.
- Adjust inputs to analyze different scenarios for academic or professional applications.
Applications of First Law Analysis
- Engineering Education: Solve homework problems and understand energy conservation in systems.
- Thermodynamic Research: Analyze energy changes in chemical or physical processes.
- Process Engineering: Evaluate heat transfer and work in engines, power plants, and industrial systems.
- Design Verification: Confirm calculations in simulations and experiments.