Background radiation

• What is the main purpose of the BBC Homepage?

  To provide access to news, sport, and educational resources.
• What is background radiation?

  Low-level radiation that is always present from natural and man-made sources.
• Why is it important to handle radioactive sources carefully?

  To ensure safety and minimize exposure to harmful radiation.
• What factors influence the amount of radiation a person is exposed to?

  Where they live, what job they do, and other personal circumstances.
• What are some natural sources of background radiation?

  Cosmic rays, radioactive rocks, and radon gas.
• How does background radiation affect people?

  It mainly affects people through irradiation and a small amount through contamination.
• What is irradiation?

  The process of exposing an object to a source of radiation.
• What does it mean for a substance to be contaminated?

  A substance is contaminated if another substance is mixed or dispersed within it.
• What is a radioisotope?

  An isotope of an atom that releases ionizing radiation.
• What is the simplest measure of radioactivity?

  The Becquerel (Bq).
• What does the activity of a radioactive source measure?

  The number of decays of a radioactive element per second.
• What is the activity of a source that emits one particle per second?

  One Becquerel (1 Bq).
• How do alpha and beta particles differ in terms of their effects on the human body?

  Alpha particles cause more damage over a shorter distance, while beta particles have more energy but less damaging potential.
• What is ionisation?

  The process by which electrons can be added or removed from an atom to create an ion.
• Why do alpha particles cause more damage than beta particles?

  Because alpha particles are larger and have a greater ionisation power.
• How does the energy of beta particles compare to that of alpha particles?

  Beta particles have more energy but cause less damage due to their lower ionisation power.
• What is the significance of measuring radioactivity in Becquerels?

  It allows scientists to quantify the activity of radioactive materials.
• What is the effect of emitted energy on the internal energy of a radioactive material?

  The internal energy of the material will decrease.