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Particles in Electric or Magnetic Fields
Alpha particles have a positive charge and beta particles have a negative charge. So when they are
put in a magnetic or electrical field, they will deflect away from each other. This is because of their
opposite charges. Alpha particles have a greater positive charge, and feel the force in the field more,
but they deflect less because their mass is a lot higher than beta particles. Therefore, the beta
particles will deflect a lot more in comparison to alpha particles.
Gamma rays will not deflect at all because they are neutral so electric or magnetic fields have no
effect on gamma rays.
You can see above that the beta particle has deflected most. Then the alpha particle has deflected a
bit. The gamma ray is going straight ahead.