Powerpoint lecture covering the following in a modern, concise format:

Specification Point 7.10 - Explain the sources of background radiation from Earth and space.

Specification Point 7.11 - Know that the activity of a radioactive source decreases over a period of time and is measured in becquerels.

Specification Point 7.12 - Know the definition of the term half-life and understand that it is different for different radioactive isotopes.

Specification Point 7.13 - Use the concept of the half-life to carry out simple calculations on activity, including graphical methods.

Specification Point 7.14 - Describe uses of radioactivity in industry and medicine.

Specification Point 7.15 - Describe the difference between contamination and irradiation.

Specification Point 7.16 - Describe the dangers of ionising radiations and how to dispose of radioactive waste.

Complete set of Chapter 7 Lectures are available.