Alpha (a)

Beta (b)

Gamma (g)

Nature
 Helium nuclei (Proof Experiment) Fast-moving electrons Electromagnetic waves

Charge
 +2 -1 No charge

Mass
 Heaviest Lighter No mass

Speed
 Up to 1/10 speed of light Up to 9/10 speed of light Speed of light

Ionising Ability
 Strong Weak (1/10 of alpha) Very weak (1/10000 of alpha)

Pentrating Power
 Not penetrating: stopped by a sheet of paper Penetrating: stopped by 5mm of aluminium Highly penetrating never fully absorbed: reduced to half by 25mm of lead

Effect of magnetic field
 Very small deflection Large deflection No deflection

Detectors
  • Photographic film
  • Cloud chamber
  • Spark counter
  • Thin window GM tube
  • Photographic film
  • Cloud chamber
  • GM tube
  • Photographic film
  • Cloud chamber
  • GM tube

Energy (MeV)
 0.5-1.0 0.01-10 0.01-10

MeV =Mega electron Volt

 

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