Science Zone

How Ship's Floatation on Water Is Possible

<div xmlns='http://www.w3.org/1999/xhtml'>Why is that an iron Rod sink in water? But imagine a ship made by an iron rod does not sink? 
 
This question was asked by one of our readers and I considered it worthy of a blog post. 
 
The ability of an object to float on water depends on factors such as the nature of object, the surface area and so on. 
Let's consider the principle of floatation popularly known as Archimedes's principle, he noted that for an object to float on water, the weight of object must equal the upthrust on the object when immersed in water. 
However it's most important to know that an object only floats on a water if and only if the weight of the body equals the upthrust before it's fully immersed in a liquid. 
Have you witnessed that it's possible for a rubber cup containing water to sink in a bucket of water and a steel cup to float. The both can sink and float based on the condition stated above. 
 
Coming back to your question, you pointed out that iron sinks and so should anything made of it. That's wrong. 
Here we are talking of the surface area, ship has a large surface area and thus before it can sink, it has to displace a large amount of water and its weight on the water leads to increase in upthrust on the ship and thus the weight and the upthrust equals each other. 
The effect of surface area can be seen in this way. 
We know if a stone and a paper are fallen at a height and at the same time in a vacuum, they land the same time. Why that's is not true if done in the atmosphere is that the stone has small surface area unlike the paper. 
 
So the paper has to overcome more resistance from the air i.e displace more air to land compared to the stone.</div>

How Ship's Floatation on Water Is Possible

Why is that an iron Rod sink in water? But imagine a ship made by an iron rod does not sink? This question was asked by one of our readers and I considered it worthy of a blog post. The ability of an…

22 Apr 2015

EVER WONDER WHY BIRDS FLY IN V FORMATION

<div xmlns='http://www.w3.org/1999/xhtml'>I stood gazing in wonder when a "V" flew past over me. Not actually a letter "V", rather a flock of birds in V formation. Still watching the beautiful scenery created by those birds in the sky, I noticed the one at the rear fly past others and replaced the leader. 
 
That's awesome I said having realized they possibly continued to change position when the leader is weak as our winged friends continue their migration 
 
Why do birds migrate? 
Why do birds fly in V formation? 
Why do the even prefer V shape? 
 
Away we flock with them to find the answer... 
 
Though not all birds migrate but more than half do. They are referred as migratory birds. 
Reasons why birds migrate to a different habitat vary but shouldn't be far from availability of food or for survival purpose i.e they respond to stimuli such as changes in weather. 
 
Flying in V formation is in fact a characteristic of migratory birds. 
Reason; to save energy during their long journey. 
 
Funny enough! birds migrate several kilometers away from their habitat. Don't be surprised why they mainly feed on grains because the grains provide the energy they burn up during their flight. Flying consumes a lot energy even a pilot can tell you that. 
 
Thanks to nature that has this amazing feature bestowed to our winged friends to enable their aerial adaptation. 
 
In the northern hemisphere, many birds migrate south during the winter months when the weather becomes too cold for them to survive in their northern habitats. Once spring arrives, the birds return to their homes. Equally as varied as the reasons for migrating are the ways in which different migratory birds make their journey. Some birds migrate alone, others travel in pairs and many move in large flocks. Some birds often migrate in swarms, while larger birds, such as geese,migrate in formation. 
 
Many times this migration takes the form of the letter V. 
Why? 
The reason birds prefer to fly in a V shape has puzzled researchers for many years. There are two general theories to explain the V-shaped phenomenon. The most accepted theory is that the formation of a flock influences aerodynamics, making it easier for the birds to fly. As the birds flap their wings, the air flowing off their wing tips gives birds in the back of the V an extra lift. 
 
This reduces the amount of energy the birds need to fly. Over the course of the migration, birds take turns leading the front of the V, the most difficult position. When a bird is tired of leading, it falls to the rear of the V, where there is the least wind resistance. Rotating through various positions in the V maximizes the use of each bird’s energy, allowing flocks to fly for long periods of time without having to stop. 
 
The second theory suggests flying in a V offers each bird an unimpaired line of sight as the flick flies through the air. This makes it easier for the birds to keep track of each member of the flock. Groups of fighter pilots often arrange their planes in V formation for the same reason.</div>

EVER WONDER WHY BIRDS FLY IN V FORMATION

I stood gazing in wonder when a "V" flew past over me. Not actually a letter "V", rather a flock of birds in V formation. Still watching the beautiful scenery created by those birds in the sky, I noti…

12 Apr 2015