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Why do We Cup Our Hands When We Shout?
“Go on Sanjay, go on,” we shouted. It was the annual sports meet in our school and the 100 metres sprint was on. The White House runner Deepak was giving our Blue House sprinter, Sanjay, tough competition. As the sprinters neared the finishing line, and the shouts turned into screams, I noticed something remarkable. Everyone had cupped their hands around their mouths while shouting. The gesture caught my attention. I had seen that kind of a hand movement in plays and folk dances....
Why do Meteorites Strike the Earth?
On a hot summer afternoon, I sat down with my elder brother to play carom. I took the first strike and pocketed two coins. Then I did a little war dance. Wow! Suddenly dada (Bengali for elder brother) had an idea. “How would it be if a fast-travelling object hit the earth? Quite like the way the striker hit the coins.” I was amused. “How is it possible? The earth is so huge. Anyway there aren’t any strikers flying around in the solar system?...
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....
Tale of the Woolly Mammoth
Almost 20,000 years ago, a group of hunting tribesmen attacked an enormous elephant like animal called the Woolly Mammoth. A fierce battle was fought as the prehistoric tribesmen armed with spears and stone catapults attacked the Mammoth. The Mammoth, almost twice the size of a modern African Elephant, charged and stomped. And as a spear pierced its heart, it gave one last heart wrenching cry and fell to the ground with a loud thud, a sound that reverberated through the mountains....
What is the Trail behind a Jet?
When we were small, we used to look up to the sky and often see a white trail left by a jet aircraft. Rocket! Rocket! We used to yell, jump up with joy, clap our hands and strain our eyes as the ‘rocket’ disappeared into the horizon. Soon, the white streak would change into a broken, twisted cloud path. And we were told that it was the fairies’ trail. What is the Trail behind a Jet?...
Why do Airplanes have Wings?
I remember my trip to Goa. The flight was scheduled for six a.m. As the aeroplane taxied on the runway it gained speed. I felt a kick in the stomach and then we were airborne. It was my first flight and I was very excited. My father who was sitting next to me, asked, “Can you tell me how the aircraft flies?” “Because of wings,” I replied promptly. But I could not tell him what the wings do to make a plane fly....
What is the Secret of the Windmill?
It was a particularly windy day in late July when my cousin and I sat down to make a pinwheel. The paper was folded into a wheel, the pin inserted at the heart of it and the entire structure fixed to the broomstick. As our pinwheel took shape we ran out braving the sun and the hot wind. The pinwheel caught the wind and rotated. Seeing it, our hearts pin-wheeled as well. Energy from wind...
What is Ham Radio?
Consider this, your state has been hit by a cyclone with wind speeds measuring 300 kilometres per hour. All modern means of communication – telephone, cellphone, wireless sets – lie dead as the cyclone has destroyed all connecting stations and links. This is what happened during the Orissa cyclone. All communication links broke down as dish antennas, radio stations, telephone lines, satellite links were destroyed. There was no way people could contact the outside world. This was when a bunch of amateurs, students and radio enthusiasts got together to set up something called an amateur radio or ham radio station....
How do Animals Communicate?
Humans have invented new and advanced ways of communicating with each other. Television, radio, telephones and of course email. You will be surprised to know that animals who seem to have very simple methods of communication – using their bodies and voices – are also capable of long distance communication. How do Animals Communicate? [Illustration by Shinod AP] Foot stomping and low frequency rumbling created by elephants can travel upto 20 miles and is used by elephants to signal other herds or members, says an article in the Hindu newspaper....
Do Whales and Dolphins see Blue?
Dolphins and whales live in the deep blue sea, but strangely these animals are not able to see the colour blue! Leo Peichl of the Max Planck Institute for Brain Research in Frankfurt and his colleagues discovered during routine tests that seals do not respond to the blue colour. Intrigued, they carried out similar tests on few other species, such as dolphins and whales, and found the same results. According to fossil evidence, whales are believed to have descended from a four-legged primitive ungulate (hoofed mammal) which lived on land and was similar to the modern day hippopotamus....