Based on the following questions and answers, what conclusion can be drawn?

1. What are the effects of changing the position of G on the position of the metacenter? Is this what you expected? Say why. (Comment on the effects of changing the position of G on the position of the metacenter.)

Raising the vessel's center of gravity (G) causes a decrease in the metacentric height (GM) and thereby smaller values of the righting levers (GZ). If the vessel's center of gravity (G) is above the metacenter (M), the vessel is in an unstable equilibrium. The vessel has a negative GM and is not able to float upright.

2. Are the values of GM at the lowest values more accurate or less accurate? Is this what you expected? Explain why.

The metacentric height (GM) is a measurement of the initial static stability of a floating body. It is calculated as the distance between the center of gravity of a ship and its metacenter. A larger metacentric height implies greater initial stability against overturning. Metacentric height also influences the natural period of rolling of a hull, with very large metacentric heights being associated with shorter periods of roll which are uncomfortable for passengers. Hence, a sufficiently, but not excessively, high metacentric height is considered ideal for passenger ships.

3. What is the meaning of the relative error? What is its ideal value? Say why.

Relative error (RE)when used as a measure of precisionis the ratio of the absolute error of a measurement to the measurement being taken. In other words, this type of error is relative to the size of the item being measured. RE is expressed as a percentage and has no units.

4. List and explain all possible causes of any discrepancies between the experimental and theoretical results for the metacentric height.

To find out the metacenter height by experimental method - metacenter depends on body shape also but in theoretical ship shape does not affect inclining test. The metacentric height is normally estimated during the design of a ship but can be determined by an inclining test once it has been built. This can also be done when a ship or offshore floating platform is in service. It can be calculated by theoretical formulas based on the shape of the structure.

5. Explain how unstable equilibrium might be achieved.

An unstable equilibrium is caused when the vertical position of G is higher than the position of transverse metacenter (M). So, when the ship heels to an angle (say theta- ), the center of buoyancy (B) now shifts to B1. GM = 0 means the ship is neutrally stable. GM < 0 means the ship is unstable.

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Based on the provided questions and answers the following conclusions can be drawn 1 Changing the position of the vessels center of gravity G affects ... View the full answer