The human eye uses light to see. Light bounces off our surroundings and into our eye through our pupil, the black hole at the center. A picture forms on our retina, the lining at the back of the eye. Our brain makes sense out of what we see. Without light, there is nothing to enter our retina and therefore we …
Read More »Why can’t the Sun melt Snow?
There are some things in nature that have a great capacity to toss back or reflect a great deal of the sun’s light that falls on them. One of them is snow. Newly formed snow reflects about 90 per cent of the sunlight that falls upon it. This means that the sun is powerless to melt clean snow. And when …
Read More »Why are zodiac signs named after animals?
The term ‘zodiac’ stands for animals. However, all zodiac signs do not represent animals, like Libra is represented by a balance. Astrologically and astronomically, zodiac signs are representative of various pattern formed by stars. Ancient astronomers had named each zodiac by the shape formed by a few important and bright stars resembling the shape of animals, located in that section …
Read More »Why are viruses at the borderline of living and non-living things?
A virus has a very simple composition. It has a protein sheath inside which there is a strand of DNA. A virus shows some properties akin to living organisms. However, unlike other organisms, they show some properties that are akin to non-living things. They can undergo crystallization and in that form, survive for billions of years. They can survive very …
Read More »Why are there waves on the sea?
Only very rarely are the seas completely still. These were the times that sailors on the old sailing ships feared the most – even more than they feared the worst storms. They became becalmed, which meant that no wind was blowing to fill the great sails to carry them to their next port of call. The sea would be motionless …
Read More »Why are stars grouped in constellations?
People who gazed at the skies in ancient times believed that they could see the shapes of animals and peoples traced out in the stars. These star groups, or constellations, have the Latin names of the shapes, and astronomers use the names in identifying stars. But the stars in a constellation do not belong to any actual group in space …
Read More »Why are Some Plants Non-vegetarian?
Are you scared of going to the forest because you think there are man-eating tigers in the forest? What would you do if there were man-eating plants too? Don’t worry. Man-eating plants do not exist. But insect and animal-eating plants do. They are what you would call non-vegetarian plants. In fact, there are 500 varieties of plant species that trap …
Read More »Why are some people left-handed?
When a person is left-handed, all it means is that they can do certain things better with the left side of their body than with the right. You may have noticed that some people write with their left hand instead of their right, and that they hold their knife in their left hand, and other similar things. This is not …
Read More »Why are some people diabetic?
Diabetics are people who suffer from diabetes. The main kind of diabetes affects the pancreas, which is gland that produces a hormone called insulin. This hormone controls the amount of sugar in the blood, which provides the energy for the body. In diabetes, insufficient insulin is produced and the sugar level is uncontrolled, resulting in illness. Diabetes usually cannot be …
Read More »Why are some metals chromium plated?
Some metals are chromium plated to make them look more attractive and to prevent them from corroding or rusting. Chromium is a silver white, hard, brittle metal which was discovered in 1798 by N.L. Vauquelin. Its non-corrosive, high strength, heat resistant characteristics are utilized in alloys and as an electroplated coating. In electroplating, the article to be plated is connected …
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