Lesson 13 radiation

• What is an alpha particle composed of?

  2 protons and 2 neutrons
• Why is the ionizing power of alpha particles considered high?

  Because they easily strip electrons from atoms, creating ions
• What is the penetrating power of alpha particles?

  Low
• What can stop alpha particles?

  A sheet of paper, skin, or a few centimeters of air
• What is the range of alpha particles in air?

  1 to 2 cm
• What are the uses of alpha particles?

  • Smoke detectors: Ionize air; smoke disrupts this, triggering the alarm.
• What is a beta particle?

  A high-speed electron emitted from the nucleus
• What happens during the emission of a beta particle?

  A neutron converts into a proton
• What is the ionizing power of beta particles?

  Medium
• What materials can stop beta particles?

  Typically stopped by aluminum or plastic
• What is the range of beta particles in air?

  Approximately 15 cm
• What are the uses of beta particles?

  • Medical radiation therapy: Target and damage cancerous cells.
  • Thickness testing: Measure material thickness in industries.
• What is gamma radiation?

  A type of electromagnetic radiation released from an unstable atomic nucleus
• How does gamma radiation compare to X-rays?

  It is similar but originates from nuclear decay
• What is the ionizing power of gamma rays?

  Low
• What is the penetrating power of gamma rays?

  High
• What materials are required to block gamma rays effectively?

  Thick lead or concrete
• What is the range of gamma rays in air?

  Can travel many kilometers
• What are the uses of gamma radiation?

  • Medical imaging: Used in diagnostic imaging such as PET scans.
  • Industrial inspection: Inspect welds and materials for defects.
• What is half-life?

  The time it takes for half of the unstable nuclei in a sample to decay
• Why is the half-life important?

  It allows prediction of how long a radioactive substance will remain active
• What are the applications of half-life?

  • Radioactive dating (e.g., Carbon-14 dating in archaeology).
  • Determining the safety of radioactive waste disposal.
• What is the half-life of Carbon-14?

  5,730 years
• What is the half-life of Iodine-131?

  8 days
• Why is Iodine-131 useful in medical treatments?

  It decays quickly after use