Re: In figuring the buoyancy of an object is water tension an important factor?

Dear Melody,

To answer your first question, surface tension of water is negligible when compared to the weight of a large platform plus 150 people. The important factors in buoyancy are the total weight of the floating object and the weight of the water displaced.

Other general design considerations include, but are not limited to:

• Stability: The dance floor must be designed to not tilt significantly. Important considerations include the location of the center of mass (which can move), water displacement, and the effect of moderate-size waves.
• Movement: Is the dance floor designed to be moved, for example, by an motor and engine? If so, placement of the motor, motor power, and aerodynamics of the floating floor need to analyzed.
• Safety: In any engineering project, this is a primary factor. Stability, discussed above, is one aspect of safety. Others include common-sense safety precautions, such as guardrails, lifeboats (if necessary), etc. Environmental impact of the entire design should also be considered (a form of public safety).

Usually, my MADSci responses also list other online references, but I couldn't locate any specific resources on designing such an object. A friend of mine suggested looking into catamarans as a possible design. In any case, I would strongly suggest seeking the advice of a local civil or maritime engineer. Good luck with your class project.

Your MAD Scientist,
Raymond Cheong