Radiation Pressure Calculator

Multiply normal incident intensity by the selected ideal momentum factor and divide by light speed. Partial reflection and absorption require a measured momentum-transfer model between these bounds. The calculator evaluates only the stated idealized equation and supplied values. It does not infer missing conditions, choose an experimental convention, or certify a measurement. Keep every quantity in the displayed unit and verify the model against the physical setup before relying on the result.

The pressure is momentum flux normal to the ideal surface, not thermal pressure or total force without an illuminated area. Multiplying pressure by a suitable projected area gives force only under uniform normal illumination. Numerical precision does not imply experimental accuracy. Compare the output with scale, sign, limiting cases, and an independent source, then account for uncertainty in measured inputs and constants before using it in laboratory, engineering, or safety-sensitive work.

Radiation is normally incident and the surface is represented as perfectly absorbing or specularly reflecting. It excludes oblique incidence, transmission, scattering, beam profiles, heating, material deformation, and relativistic motion. The result is educational and is not a simulation, calibration, engineering approval, or safety determination. More complete models may require geometry, material response, boundary conditions, relativistic frames, dispersion, losses, uncertainty propagation, or numerical field solutions not represented by these inputs.