takes for the number of Define the term MS 1c, 3d remaining ones until nuclei of the isotope in a none are left. (HT only) Calculate the net sample to halve, or the decline, expressed as a in average time it takes for the a radioactive emission after a count rate from a sample given number of half-lives. containing a radioactive isotope to fall to half its initial level. 4.3.2.4 Alpha particles are absorbed Compare the 1 Draw a diagram to illustrate Demonstrate the by just a few millimetres of penetration of the the penetration of the different radioactive sources and air or by a thin sheet of different types of of nuclear radiation and their penetration into paper. nuclear radiation and their ionising power. different materials. their ionising power. Beta particles can pass Discuss the alleged alpha through air and paper but are (polonium) radiation poisoning completely absorbed by a of Alexander Litvinenko. sheet of metal just a few millimetres thick. Gamma rays pass through most materials easily but are absorbed by a thick sheet of lead or by several metres of concrete. 4.3.2.5 Irradiation is the process of Describe the process 1 Ask students to work out how Depending on the exposing an object to of irradiation. they would transport soft fruit season, have some radiation from an outside for weeks. examples of soft fruit left Describe how source. Irradiation can be in a warm cupboard for radioactive
takes for the number of nuclei of the isotope in a sample to halve, or the average time it takes for the count rate from a sample containing a radioactive isotope to fall to half its initial level. Define the term MS 1c, 3d (HT only) Calculate the net decline, expressed as a in a radioactive emission after a given number of half-lives. remaining ones until none are left. 4.3.2.4 Alpha particles are absorbed by just a few millimetres of air or by a thin sheet of paper. Beta particles can pass through air and paper but are completely absorbed by a sheet of metal just a few millimetres thick. Gamma rays pass through most materials easily but are absorbed by a thick sheet of lead or by several metres of concrete. Compare the penetration of the different types of nuclear radiation and their ionising power. 1 Draw a diagram to illustrate the penetration of the different of nuclear radiation and their ionising power. Discuss the alleged alpha (polonium) radiation poisoning of Alexander Litvinenko. Demonstrate the radioactive sources and their penetration into different materials. 4.3.2.5 Irradiation is the process of exposing an object to radiation from an outside source. Irradiation can be Describe the process of irradiation. Describe how radioactive 1 Ask students to work out how they would transport soft fruit for weeks. Depending on the season, have some examples of soft fruit left in a warm cupboard for
AQA-8465-SOW-IWE.DOCX