Father of Radioactivity is

Henry Becquerel was the first person to discover evidence of radioactivity, received the 1903 Nobel Prize in Physics. The SI unit for radioactivity, the becquerel (Bq), is named after him. W.C. Roentgen was a German mechanical engineer and physicist, who, on 8 November 1895, produced and detected electromagnetic radiation in a wavelength range known as X-rays or Rontgen rays, an achievement that earned him the first Nobel Prize in Physics in 1901. Godfrey Hounsfield was an English electrical engineer who shared the 1979 Nobel Prize for Physiology or Medicine with Allan McLeod Cormack for his pa in developing the diagnostic technique of X-ray computed tomography(CT). Henri Becquerel