Introduction to Radiation

1. This particle is a helium nucleus containing two protons and two neutrons.
5. This scientist accidentally discovered radioactivity while studying phosphorescence.
7. This physicist discovered the neutron in 1932.
8. The Curies discovered this element which is more active than uranium.
13. This process occurs when radiation removes electrons from neutral atoms.
15. This property describes the ability of radiation to pass through matter.
16. This particle has the mass of an electron but carries a positive charge.
18. Henri Becquerel left this element on a photographic plate in a dark drawer.
19. This scientist co invented the counter used to detect ionising radiation.
20. This type of chamber makes the paths of ionising radiation visible to the eye.

2. This dense metal shields users from high energy gamma rays.
3. This metal foil stops beta radiation but allows gamma rays to pass.
4. This high energy electromagnetic radiation has zero mass and zero charge.
6. This term describes the maximum distance a particle travels through a material.
9. This word describes an unstable nucleus that spontaneously emits energy.
10. This uranium rich mineral led to the discovery of radioactivity in 1896.
11. The Curies isolated this radioactive element and named it after Poland.
12. This neutral subatomic particle resides within the nucleus.
14. This radiation consists of a fast moving electron or a positron.
17. This physicist won two Nobel Prizes for her research into radioactive rays.