Soft drinks Many soft drinks contain a chemically manufactured sweetener called aspartame. Aspartame tastes very like sugar but is much sweeter than sugar. This means that only tiny amounts need to be added to a drink to make it taste sweet. It is used in so-called ‘diet’ drinks. The sweetness of aspartame was discovered in 1965 by James Schlatter. There is an ongoing debate about health risks associated with the consumption of aspartame.
Fig. 8 Aspartame is used to replace sugar. 1.4 The physical world
The physical world focuses on the interaction between materials and different forms of energy, such as heat, light and electricity. Understanding this aspect of the physical world has given rise to many of the technologies which we use in our lives.
Microwave technology Microwave radiation occurs naturally in the physical world and can now be produced by machines. Microwaves are used in microwave ovens. They are also used to send signals from mobile phones.
Fig. 9 Energy comes in many different forms.
Fig. 10 Microwave radiation cooks food in a microwave oven.
Laser technology Lasers were first developed in the 1960s. At the time they were described as ‘a solution looking for a problem’ because initially they did not have any specific use. Today, laser technology is used in many different ways, for example in devices such as CD/DVD players and supermarket scanners. It is also used to perform surgical operations such as laser eye surgery.
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Fig. 11 Laser technology is used in surgery, CD players and many other areas.
