Waves
A wave is a phenomenon whereby energy is moved without the transference of any material. X-rays, ultraviolet rays, light and radio waves all travel at the same speed through a vacuum.
The Kinetic Theory Of Matter
When a red hot piece of iron cools down, it transfers energy to its surroundings in three possible ways: conduction, convection or radiation.
The Four Fundamental Forces
The interactions between matter can be explained by four forces.
States of Matter
Special And General Theories Of Relativity
Special theory of relativity was formulated by Einstein.
Radioactivity
Radioactivity was gradually understood in terms of the disintegration of atomic nuclei. The three types of radiation are alpha decay, beta decay and gamma decay. Alpha radiation occurs when an unstable nucleus breaks down so as to eject a fast-moving nucleus of helium, which consists of two protons and two neutrons.
Nuclear Fission And Fusion
Otto Hahn and Fritz Strassmann (1902-80) discovered nuclear fission in 1938. When an isotope of uranium-235 was bombarded with neutrons, it split into two lighter nuclei along with, on average, three neutrons. These neutrons were capable of bombarding and splitting other nuclei, causing more fission to take place.
Motion And Mechanics
Kinematics covers a broad range of topics, from bodies falling to earth, to the description of bodies moving in a straight line, to circular motion.
Measurement Units
Introduction to Physics
Physics is the study of the basic laws that govern matter.
Heat and Work
Modern physics sees heat as energy collectively possessed by the particles making up a gas, liquid or solid. A body which possesses energy has the ability to do work.
Electromagnetism
Electromagnetism is the study of the effects caused by stationary and moving electric charges.
Electric Current
In the late 1790s, Count Alessandro Volta made the first battery. The first practical primary cell (non-rechargeable) was produced by John Frederic Daniell (1790-1845) in 1836, using zinc and copper electrodes. This was followed by the first secondary (rechargeable) cell invented by Gaston Plante (1834-89) in 1859.
Atomic Theories
John Dalton revolutionized science in 1803 when he hypothesized that atoms of different chemical elements, such as hydrogen and oxygen, had different characteristic masses. J.J. Thomson discovered the first subatomic particle -the electron - in 1897.
