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TSR Wiki > Study Help > Subjects and Revision > Revision Notes > Physics > Alpha, Beta and Gamma Radiation

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Contents 1 Alpha rays (or particles) 2 Beta rays (or particles) 3 Gamma rays 4 Comments

Alpha rays (or particles)

• helium nuclei – 42 He
• Big and heavy (slow moving)
• Don’t penetrate into materials
• Very ionising
• Blocked by paper

Beta rays (or particles)

• high-energy electrons – -10 e
• Quite small, move quite fast
• Penetrate materials moderately
• Ionise moderately
• (for every beta particle emitted, a neutron turns into a proton in the nucleus)
• Blocked by thin Aluminium

Gamma rays

• electromagnetic waves with shorter wavelength (higher frequency) than x-rays
• Opposite to alpha
• Penetrate materials well
• Weakly ionising
• When hit something do damage
• Blocked by thick lead

Comments