Do You Know How Rugby Football Began?
For thousands of years, people have played games in which they kick a ball towards a fixed point. Most cultures had games in which a person had to kick or carry a ball through a goal or across a line which the opponent had to defend.
Do You Know What Rheumatic Fever Is?
Rheumatic fever is not related to rheumatism. It is a disease of the heart. Round bacteria called 'streptococci' attack the heart and weaken it. Rheumatic fever usually follows some other problem, such as a nose or throat infection.
What Is Energy?
You use energy in many different ways. You use it to cook your food. You use it to get to school or work. And you use it to light up a dark place. In fact, you use a lot of energy every day. Even though you use energy all the time, you probably don't think about it much.
Do You Know Why Our Cities Are Growing So Fast?
In most poor countries people who live in the rural areas lead a very hard life. Also, because of the demand from large cities, rural areas are spoilt by mines, dams and factories. These affect sources of drinking water and poison farmland.
Do You Know Why A Balloon Bursts If It Rises Too High?
Air exerts pressure on everything because of its weight. If you climb high up a mountain, there is less air pressure because there are fewer layers of air above you. Some balloons are filled with a gas like helium which is lighter than air. If you release a helium balloon, it quickly rises up.
