Discovery History of Radioactivity

The Phenomenon of Radioactivity was discovered almost accidentally by a French Chemist Henry Bequrrel in 1896 when he placed a photographic plate with a piece of uranium in a closed dark drawer in a room. When he saw that photographic plate on the next morning he saw that it was completely fogged and this can only be done by some radiation. By this incident he came to the concussion that uranium emit some type of invisible radiation. And such substance which emit such type of radioactive radiation are known as radio active substance. Later it was found that thorium also emit such type of radiation.
Later in 1899, Ernest Rutherford discovered that uranium atom produces three different kind of radiations. He distinguishes these radiation on the basis of their penetration power and named them as alpha, beta and gamma radiation after the first three later of Greek alphabets
We will discuss about this radiations in later posts.