What is a nuclear reaction? There are two kinds of nuclear reactions. Both produce great amounts of energy. In nuclear fusion, two nuclei collide and combine into one larger nucleus. In nuclear fission, neutrons are used to bombard the nucleus of an atom which causes...
How did small dinosaurs defend themselves from enemies? The Scutellosaurus was a small dinosaur the size of a domestic cat. But it was a tough fighter when confronted by big dinosaurs. It had rows of small bony knobs along its back and tail. These gave...
What did the Romans trade? The trade routes of Romans extended throughout Europe, China and Indi Their ships were loaded with things like wine, olive oil, farm products and works of art. They traded these for exotic goods like wild animals, ivory and silk.
Did the Celts raise cattle? Celts farmed land. They needed meat to see them through harsh winters. So they raised cattle. One of their important feasts was the feast of Beltane on May 1. On this day, Celtic priests called druids chased cattle through bonfires...
What makes water evaporate? Water is a liquid. At the surface of the water are molecules. When water is heated, the molecules move so fast that they fly into space, escaping the force of cohesion which held them together. At this point water becomes gas...
What are the different kinds of fossils? It is not just dinosaur bones and teeth that have been fossilized. There are fossil imprints of their scaly skin, footprints, and nests of eggs. Fossilized dung has also been found. Sometimes fossils form when insects get trapped...
What are hallucinations? Sometimes people see things that are not really there like ghosts or other strange creatures or they hear voices. Unlike illusions, hallucinations are not the result of some external stimulation to the eyes or the senses. For instance, a mirage is an...
Why is the agave called the century plant? A mistaken belief is the reason why the agave plant is called the century plant. People thought that the plant bloomed only when it is 100 years old. But blooming happens within a few years unless it...
What are the uses of vitamin C? Vitamins are formed by plants or animals. Lack of vitamins can result in diseases. Vitamin C is found in fresh green leaves, roots, stems, buds and pods of plants. It prevents the disease scurvy. During the 17th century,...
Did male and female dinosaurs have different colours? It is quite likely that this was the case. Males and females are differently coloured in present day animals too. The males are often brightly coloured to attract females or warn off other males. The females have...
