My Science School

Bubbles are round because one of the laws of science arranges for them to be round. This law governs all sorts of things. Bubbles are just one group controlled by it. According to this scientific law, any arrangement of matter in which particles can move about always make a shape that requires the smallest amount of energy. That makes sense. There are an awful lot of people who wish they could live like that too.

Take water as an example. If you spill it on the floor, it tries to spread to the thinnest layer it can. That uses the least energy. Rubber bands are the same. Stretch them and they will try to contract again because that reduces the total energy output to its minimum.

Following this principle, bubbles are pulled into shape by surface tension – the same force that lets a needle float on top of a glass of water, Surface tension pulls on the surface of a bubble as it constantly tries to reduce its area. By doing this, it also reduces the amount of energy needed to maintain the bubble’s shape.

The round shape of a sphere is the most energy-efficient for enclosing the greatest area from a given line round the outside. So surface tension pulls the bubble to this shape until it cannot pull it further.

Imagine it was possible to blow a cubic soap bubble. Surface tension would get to work on this straightway. By tugging at the corners, it would round them more and more until it had turned the cube into the energy-efficient sphere which we recognize as a bubble.

 

Picture Credit : Google

Bubbles are round because one of the laws of science arranges for them to be round. This law governs all sorts of things. Bubbles are just one group controlled by it. According to this scientific law, any arrangement of matter in which particles can move about always make a shape that requires the smallest amount of energy. That makes sense. There are an awful lot of people who wish they could live like that too.

Take water as an example. If you spill it on the floor, it tries to spread to the thinnest layer it can. That uses the least energy. Rubber bands are the same. Stretch them and they will try to contract again because that reduces the total energy output to its minimum.

Following this principle, bubbles are pulled into shape by surface tension – the same force that lets a needle float on top of a glass of water, Surface tension pulls on the surface of a bubble as it constantly tries to reduce its area. By doing this, it also reduces the amount of energy needed to maintain the bubble’s shape.

The round shape of a sphere is the most energy-efficient for enclosing the greatest area from a given line round the outside. So surface tension pulls the bubble to this shape until it cannot pull it further.

Imagine it was possible to blow a cubic soap bubble. Surface tension would get to work on this straightway. By tugging at the corners, it would round them more and more until it had turned the cube into the energy-efficient sphere which we recognize as a bubble.

 

Picture Credit : Google

Seeing the sun suddenly disappear in the middle of the day most have been terrifying if you were not expecting it. Modern science tells us that these sudden disappearances are eclipses. In ancient times it must have looked as if the world was coming to an end.

One eclipse had such a startling effect it even stopped a battle in the Middle East. The year was 585 BC. On one side was an army from ancient Media. Opposing them was the army from ancient Lydia. They were locked in the thick of the battle when suddenly the sun grew dim and was blotted out. The fighting stopped. For a minute or two daytime became night-time. Then the sun began appearing again and daylight was restored. But both armies were so amazed by what they had seen that they promptly made peace.

On that occasion, and at every other solar eclipse, the moon had come directly between the earth and the sun and blocked out the sun’s light. Total eclipses, which seem like night falling, only happen over certain parts of the earth once ever fifty years. Partial eclipses, when only part of the sun’s light is hidden, happen more regularly.

 

Picture Credit : Google

Until a few years ago a lot of us had never heard of ozone layer. Today many people are worrying about what might happen if the ozone layer continues to be destroyed.

Ozone is a gas. There is a thin layer of its high above the earth’s surface. That is the ozone layer. There is also a tiny amount of ozone in the air we breathe – less than one part in a million. That is just as well. Here on earth ozone is harmful because it is poisonous. Up in the atmosphere it is quite the reverse. Up there it forms a protection against the most burning ultra violet rays from the sun. The ozone layer is a bit like a layer of super-powerful sun-screen cream – it stops the harmful rays from reaching us on earth. So you can see why it is so important. Without the sort of shield provided by the ozone layer many more people would suffer from the serious effects of the sun’s ultra-violet rays which can cause skin cancer and other disorders.

You can also see why there is such concern about the destruction of the ozone layer. Scientists have discovered that gases we produce on earth are causing the damage. The main culprits are gases used in aerosol sprays and refrigeration equipment. These are called CPC’s for short. In 1987 a hole as big as America was found in the ozone layer over Antarctica. That is why people all round the world are now starting to worry about what this could mean for the future of our planet.

 

Picture Credit : Google