Deck General · Metacentric Height (GM)
During an inclining experiment, a known weight is moved a measured distance athwartships and the vessel's heel is measured with a pendulum. The purpose of this experiment is to determine:
- AThe vessel's deadweight and TPI
- BThe position of the lightship center of gravity (KG) from which all loaded KG values are derived✓ Correct
- CThe angle of vanishing stability
- DThe free surface correction for all tanks
Explanation
The inclining experiment measures GM_exp using the formula GM = (w x d) / (W x tan theta), where w is the inclining weight, d is the shift distance, W is displacement, and theta is the heel angle. Since KM is known from the hydrostatics, KG_light = KM - GM_exp. All future KG calculations reference this lightship KG.
Authority: Stability & Trim (USCG deck topic)
Practice the full Deck General bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Deck General questions
- Metacentric Height (GM)
A vessel with a very large positive GM is described as:
- Metacentric Height (GM)
A vessel has a very small but still positive GM. This vessel is best described as:
- Metacentric Height (GM)
If KG equals KM, the vessel's initial stability is:
- Metacentric Height (GM)
The rolling period formula T = 0.44 B / sqrt(GM) shows that as GM increases, the rolling period:
- Metacentric Height (GM)
A vessel's rolling period is measured at 18 seconds. Compared to the same vessel with a period of 10 seconds, the 18-second ship has:
- Metacentric Height (GM)
In the inclining experiment formula GM = (w x d) / (W x tan θ), what does 'W' represent?