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How do Earthquakes Happen?
Simply put, the shaking of the earth caused by a sudden shifting of rocks below its surface, is called an earthquake. The earths crust or outermost layer, is not made of one single piece of solid rock. It is actually made up of independent sheets of rocks called tectonic plates. The tectonic plates of the world were mapped in the second half of the 20th century. These plates slide against each other, giving rise to physical changes in the earths topography....
How did the Pineapple get its Name?
What prompted people to call banana a banana and a pineapple a pineapple and not something else? Actually there is a reason behind the names given to each and every thing; be it a fruit, vegetable, an animal or inanimate objects like stars, planets, etc. However, sometimes the names are misleading, Take the example of pineapple: no it doesn’t come from a pine tree, nor is it an apple. When you look at a pineapple you may think you are looking at one fruit....
How Will our Sun Die?
Everything that is born must die. Not only living beings, but inanimate objects like stars too. The birth of a star The universe has massive clouds of hydrogen floating around. Sometimes, these clouds come together and form very dense and huge balls of hydrogen gas. As the clouds come close, their temperature increases. This is called a proto-star (original star). The increase in temperature triggers off nuclear reactions at the core of the star. Nuclear reactions inside the star occur when the nucleus of two hydrogen atoms fuse to produce a helium atom....
How are Earthquakes Recorded?
When an earthquake takes place, people say that it measured 6.2 or 6.5 on the scale. The scale they are referring to is the Richter Scale developed by Charles Richter in the 1930s. The Richter Scale measures the magnitude of the seismic waves or vibrations that travels across the earth’s surface. The scale uses a logarithmic formula using high-frequency data collected from seismograph stations. However, long before Richter developed his scale, a Chinese philosopher Chang Heng invented a device to measure earthquakes in 132 A....
How do Animals Camouflage?
Remember the last time you played hide and seek. You hid behind a bush while your friend tried to find you. If you were wearing a green dress, the chance of you being seen was automatically reduced as you could be mistaken for a bunch of leaves. Hide and seek is a very old game and it seems human beings are not the only ones to play it. Small fish use the tactics of the game to hide from bigger ones, while moths and butterflies use them to hide from birds and other attackers....
How Is Jelly Formed?
Had a good dinner? Now how about some cool custard with jelly on the side for dessert? Doesn’t the jelly look inviting, a transparent red-coloured blob sitting pretty on the plate, making you long to dig your spoon into it? Called Jell-O in the United States of America, jelly changes shape with the change in temperature. It stays sets at room temperature, which is between 0 degrees and 20 degree C. Warm it to about 27 degree C and watch it disintegrate into a watery mixture....
How Did the Indian Postal Service Start?
Although methods of postal delivery varied from one country to another, it is believed that in India, Emperor Chandragupta Maurya who ruled the country between 321-297 BC, was the first to introduce a form of postal communication to dispatch confidential reports to distant posts in his empire. However, the first recorded mention in history is to be found in the writings of historian Ziadduin Barni. He mentions that Ala-ud-din Khilji of the Delhi Sultanate, who ruled Delhi over 700 years ago, organized a regular horse and foot runner service called harakuras in 1296 AD....
How Does a Helicopter Hover?
It was January 26 and Rahul was terribly exited. And with good reason too. His father, a pilot in the Indian Navy, had been bestowed the rare honour of flying the newly acquired “Pawan Hans” helicopters for the Republic Day parade. Rahul couldn’t sleep the night before. He had already set his alarm clock to wake him up at 4 a.m., He wanted his mother to take him to the venue well before the scheduled time....
How did Sign Language Originate?
Have you ever seen people deep in conversation with each other without a single sound coming from their lips? Their hands and fingers move animatedly as they silently ‘speak’ sentences that sometimes you can also guess at. These people are actually conversing using sign language because they are hearing or speech impaired. Across the world, people have developed sign language to communicate with each other and with the rest of the world. Signs and gestures have always been in use....
How do Humans Balance on Two Legs?
Four-year-old Rohit couldn’t understand why his parents and grand parents were so happy on seeing his 10-month-old sister, Ruchi, take a few unsteady steps towards her favorite toy. What was so unusual about her walking -after all, he could walk and run without anyone’s help, yet no one ever clapped nor hugged him, the way they were doing it for his sister. Unable to hold his curiosity any longer he decided to talk about it to his closest friend and guide – his mother....