Density describes how much something weighs relating to its size. For example, a cubic centimetre of cork weighs less (is less dense) than a cubic centimetre of lead (which is…
Atoms (the tiny building blocks that make everything) contain protons, which have a positive charge, and electrons, which have a negative charge. Some electrons are fixed onto the atoms quite…
Heat travels in three different ways – conduction (heat travelling through a solid), convection (heat travelling through liquids and gases) and radiation (heat travelling through empty spaces). Detecting Fake Silver:…
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…
Water molecules at the surface of a glass of water are more strongly attracted to each other than to water molecules in the rest of the water. This creates a…
Hot water has more energy than cold water. This makes the water molecules move around more. Molecules that move more take up more space, but still weigh the same, so…
