(I decided to get the Monday Information blog done even though I said the important news would replace but no so dont hate) (This is science series started by me I will do 2 topics with science each Monday for maybe 6 weeks or more)
Why do we need science?
Even a 100 books couldn’t explain all the reasons why we need science? Toasters, bicycles, mobile phones, cars, light bulbs- all the gadgets and machines we use every day are the result of scientific discoveries. Houses, skyscrapers, bridges and rockets are built using science. Our knowledge of nature, light and sound comes from science. Then there is the science of predicting the weather, investigating how the stars shine and finding out why carrots are orange… In a big city almost every vehicle is built using science and technology.
Machines big and small.
Machines are everywhere! They help us do things, or make things easier. Every time you play on a see saw, you are using a machine! A lever is a stiff bar that tilts at the point called the pivot or fulcrum. The pivot of the see saw is in the middle. Using the see saw as a lever a small person can lift a big person by sitting further from the pivot. A screw is another small but useful scientific machine. It is a ridge of thread wrapped around a bar or pole. It turns a small turning movement into a powerful pulling or lifting movement. Wood screws hold together furniture or shelves. A car jack lets you lift up a whole car. Where would you be without wheels? Not going very far. The wheel is a simple machine, a circular disc that turns around its centre on a bar called an axle. Wheels carry heavy weights easily. There are giant wheels on big trucks and trains and small wheels on rollerblades. A pulley turns around like a wheel. It has a groove around its edge for a cable or rope. Lots of pulleys allow us to lift very heavy weights easily. The pulleys on a tower crane can lift huge steel girders to the top of a skyscraper. Gears are like wheels with pointed wheels around the edges. They change a fast, weak turning force into a slow powerful one- or the other way around. On a bicycle you can go up a steep hill on the lowest gear then race down the other side in highest gear.