What is the geoid-spheroid separation value at the Triangulation Station Balanacan?

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Multiple Choice

What is the geoid-spheroid separation value at the Triangulation Station Balanacan?

Geoid-spheroid separation tells you how far the geoid (the mean sea level surface used for heights) sits above or below the reference ellipsoid at a specific location. It’s the difference between ellipsoidal height from GNSS (h) and orthometric height from leveling (H): N = h − H. This value is location-dependent because the Earth’s gravity field varies across the map. For Triangulation Station Balanacan, the published separation is 0.34 meters. That means the geoid is about 34 cm higher than the reference ellipsoid there, so the orthometric height is smaller than the ellipsoidal height by 0.34 m (H = h − 0.34). If you know h and want H, subtract 0.34 m; conversely, h = H + 0.34 m. The other options would imply larger local undulations than what this station’s geoid-model data indicate, which is why 0.34 meters is the matching value for this location.

Geoid-spheroid separation tells you how far the geoid (the mean sea level surface used for heights) sits above or below the reference ellipsoid at a specific location. It’s the difference between ellipsoidal height from GNSS (h) and orthometric height from leveling (H): N = h − H. This value is location-dependent because the Earth’s gravity field varies across the map.

For Triangulation Station Balanacan, the published separation is 0.34 meters. That means the geoid is about 34 cm higher than the reference ellipsoid there, so the orthometric height is smaller than the ellipsoidal height by 0.34 m (H = h − 0.34). If you know h and want H, subtract 0.34 m; conversely, h = H + 0.34 m.

The other options would imply larger local undulations than what this station’s geoid-model data indicate, which is why 0.34 meters is the matching value for this location.

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