Physics Revision

Physics revision

Atoms:

All substances are made from atoms and each atom has a nucleus containing protons and neutrons, which are surrounded by electrons. An atomic number is the amount of protons in a atom and the elments on the perodic table are in ascending order of atomic number. The mass number of an atom is the total of protons and neutons;Atoms of the same element with different numbers of neutrons are called isotopes of that element. 

Atomic structure, There is just over one hundred different types of atom which are called elements. Atoms can join together in millions of different combinations to make all the substances on Earth and beyond.

Density:

Density is the mass per unit volume and it can be measured in many ways. The way to calculate density the most accurate way is to divide any solid, liquid or gas into kilograms by its volume (length × width × height) in cubic metres. The equation is density=mass/volume.

The unit for density…