Weighing and measuring - Terry J Jennings

Aiming to help children understand everyday objects and events around them, this book on weighing and measuring is one of a series which introduces young readers to basic scientific concepts. The book contains activities so that the reader can test out the theories for themselves.;To illustrate how a scale works there are instructions for making a spring balance using a ruler, a paper clip, string and a plastic cup suspended on string. This gives a simplistic explanation of the workings of a complicated scale. Similiarly, a weighing tool is described using a spring, two cans, a ruler and a few weighty objects. Methods for measuring firstly, small and very small objects and then, the height of a building, is given. A water clock uses the flow of water to measure time and the sand clock can be used to measure time in a similiar fashion. Both tests are done using the simplest of equipment. Finally a clear plastic bottle, food colouring and a drinking straw are used to demonstrate the functions of a thermometer.