Originally, carpets and rugs were cleaned by lifting them, taking them outside, hanging them over a line and beating them with a carpet beater (a very dusty job), or by…
Ultraviolet (UV) light is an invisible part of light. It has a shorter wavelength than violet light (see ‘Making a Rainbow: Breaking Light Into Colour’), and its name means ‘beyond…
Stalactites and stalagmites are formations of rock in underground caves. They are formed when calcium carbonate and other minerals dissolve in water running through the soil and rocks. As the…
Different solids turn into liquids (melt) at different temperatures. This temperature is described as the melting point. Some solids are made up of molecules that bind together tightly and others…
Whether they are in a bubble bath or drifting on the wind, bubbles are beautiful and fun things. Try making your own to examine the amazing properties of the simple…
As light passes through transparent objects, it bends. This can create optical illusions like disappearing bowls, bending pencils and mirages. This is called refraction, and is useful in magnifying glasses…
Water exists in three states – solid ice, liquid water and gaseous steam. Solids have a fixed shape and size. Liquids can change in shape, but have a fixed size….
Heat travels through solids by conduction (see also ‘Detecting Fake Silver: Conductivity of Metal’). Insulation can keep things warm and keep things cool by reducing heat transfer through conduction. Insulation…
Sounds are created from vibrations, whether it’s a tuning fork, the reed of a musical instrument, or sound coming from someone’s voice box. The vibrations make the air molecules move…
