Characteristics of Radioactive Emission




Ionising Effect

  • All alpha, beta and gamma emission can cause ionising effect.
  • Alpha particle has high ionizing power.Beta particle has low ionizing power.
  • Gamma ray has very low ionizing power.

Penetrating Power

Deflection in Electric Field

Deflection in Magnetic Field

  • Alpha and beta emission can be deflected by a magnetic field.
  • The direction of deflection can be determined by using Fleming’s Left Hand Rule.
  • Beta particle deflected more compare to alpha particle due to its much smaller mass.

Summary

Characteristic
Alpha Particle
Beta Particle
Gamma Ray
Symbol
α
β
γ
Nature
Nucleus of Helium
High speed electron  Electromagnetic wave
Charge
+2
-1
Neutral
Ionizing Effect
strong
weak
Very weak
Absorted by Sheet of writing paper
About 5mm of aluminium
Never fully absorded. 25mm of lead reduces intensity to half
Deflection in Electric Field
Can be deflected
Can be deflected
Not deflected
Deflection in magnetic Field
Can be deflected
Can be deflected
Not deflected
Speed
Up to 10% of the speed of light
Up to 90% of the speed of light
Speed of light