A circular log floating in water is neutrally buoyant. Our ancestors found that by having half a log with semi-circular cross section and hollowing out the interior, it became stable so that they could use it to migrate across oceans. The reasons for it to become stable are: (i) (ii) (iii) (iv) It lowers the centre of gravity G so that it is below the centre of buoyancy B. It lowers the centre of gravity G so that it is below the metacentre M. It increases the metacentric radius BM. It enables the shifting of the centre of buoyancy B laterally to produce a restoring moment when it is tilted. (A) (B) (C) (D) (i) and (ii) (ii) and (iii) (iii) and (iv) (iv) and (i)

A circular log floating in water is neutrally buoyant. Our ancestors found that by having half a log with semi-circular cross section and hollowing out the interior, it became stable so that they could use it to migrate across oceans. The reasons for it to become stable are: (i) (ii) (iii) (iv) It lowers the centre of gravity G so that it is below the centre of buoyancy B. It lowers the centre of gravity G so that it is below the metacentre M. It increases the metacentric radius BM. It enables the shifting of the centre of buoyancy B laterally to produce a restoring moment when it is tilted. (A) (B) (C) (D) (i) and (ii) (ii) and (iii) (iii) and (iv) (iv) and (i)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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