What makes a Ship Float - Archimedes Principle & Buoyancy

It was not without purpose that a genius was so excited as to jump out of his bathtub and run naked on the streets shouting Eureka! Infact so important was that discovery that even the floatation of the huge mass of a ship can be explained like a child’s play.

Introduction

We learnt about the center of gravity and centroid in our previous article. Now we will move a step further and see how a simple principle discovered centuries ago in a bath tub can be applied equally well to the vast oceans in perspective of floatation of a ship.

Archimedes Principle

The science of floatation is simple yet equally interesting to know and let me explain it for you in the simplest manner possible. Now you know that every body or object has got a volume which means that if that object is placed on the surface of the water, it will displace water which is equal in volume to the volume of the object immersed inside the surface of the water (let me add here that I am using the term water in context of sea and ships, otherwise this principle applies to all fluids).

The volume of water that has been displaced certainly possesses a certain amount of mass which is given by

Mass of water displaced = volume of water displaced * density of water

Ship Stability and the Center of Gravity

You must have read about the center of gravity of a body in your high school physics but do you know its importance in the context of ship stability in the vast oceans? Just read on to find out more!

Introduction

In the previous article we learnt how forces and moments could be acting on a body at a given point of time and how to find the net or resultant value of those forces or moments. In this article we will continue our study of ship stability by learning something about center of gravity, centroid and their relationship to stability of a ship floating in the sea.

Center of Gravity

When studying objects, forces and their inter-relationships we often tend to represent a body by a point for theoretical purposes of calculations relating to that body. This certainly is a convenient method of representation but we know that in actual situation there is hardly any body which is actually the size of a point, so how do we go about it?

Ship Stability for Navigating Officers & Marine Engineers

It is very interesting to see a huge mass of metal float seamlessly on the surface of the ocean but do you really know the science behind the floatation and stability of the ship in the midst of the vast ocean? If not, just read on to learn about it in a simplistic manner.

Introduction

In this topic we will cover the basic aspects about ship stability starting from the very fundamental concepts which will help you to grasp the subject matter with ease. Since it is vital to understand the concepts behind stability we will start with a discussion of the underlying principles and theories behind the exciting science of ship stability. Such an approach would have the double benefit of being simple to understand for normal readers while it will help you to prepare for your marine certification exams if you are a student in this field.

About Force, Net Force, Moments et al.