"physical boundary" is correct and usable in written English.
You can use this expression to refer to a tangible physical object or feature (such as a wall or a fence) that marks the edge of a particular area. For example: "The river acts as a physical boundary between the two cities."
The physical boundary is a great help to avoid the time getting derailed by drive-by meetings.
Because of the fluid nature of the staging, the boundaries, especially the physical boundary, between viewer and performer are blurred.
Then, the physical boundary conditions including initial conditions were outlined to form an integrated mathematical problem.
The men seemed to be tearing the Iron Curtain, the daunting symbol of the ideological rivalry and actual physical boundary between Communist and non-Communist Europe.
2015: An inconspicuous physical boundary, called an eruv, is completed, allowing observant Jews to carry items within its enclosure on Shabbat.
The resulting clay vesicle is a strong, spherical shell that creates a physical boundary between the water inside and the water outside.
The highly asymmetric uncertainty arises due to the conversion from the phase to the sine of the phase, and the proximity of the physical boundary.
The results indicate that the created physical boundary condition resembles the ideal SS boundary condition.
Establishing adequate technical and physical boundary conditions for a sustained nuclear fusion reaction is a challenging task.
Gap formation in forests can have impacts on forest ecosystems beyond the physical boundary of the canopy opening.
Writing in 1928, John B. Watson, one of the originators of the behaviorist school of psychology, urged parents to maintain a physical boundary between themselves and their children: "Never hug and kiss them, never let them sit on your lap.
