Nuclear Decay

The period from November 1895 to May 1896 marked the beginning of a whole new field in physics. It began with Wilhelm Röntgen’s discovery of X-rays on Nov. 8, 1895. Röntgen’s rays were quickly adopted by doctors, who began using them to diagnose bone fractures in early 1896. The discovery of X-rays also helped inspire the French physicist Henri Becquerel, who was studying phosphorescent materials, or materials that glow after exposure to light. Becquerel discovered that certain uranium salts emit radiation without any outside stimulation. With this discovery, the science of radioactivity began.

Students can explore radioactivity with the Nuclear Decay Gizmo. The Gizmo explores four common types of decay: alpha decay, beta decay, positron emission, and electron capture. After viewing an animation of each decay, students determine the resulting changes in the nucleus and write a balanced equation to summarize the nuclear reaction. It is a great introduction to a bizarre world where neutrons and protons transform into one another, high-energy gamma rays are emitted, and particles of antimatter are produced.

If you like, follow up the Nuclear Decay Gizmo with the related Isotopes, Half-Life, and Nuclear Reactions Gizmos.