MCQ Detailed View

Electric and magnetic fields exert forces on charged particles. The deflection of a particle in these fields depends on its charge and mass. In radiation physics, there are three common types of rays: alpha rays, beta rays, and gamma rays.

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  Alpha rays consist of helium nuclei (2 protons and 2 neutrons) and carry a positive charge. Because they are charged, they are deflected by both electric and magnetic fields.

  
  


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  Beta rays are fast-moving electrons or positrons, carrying a negative or positive charge. They are also deflected in electric and magnetic fields, though their deflection is much larger than alpha rays due to their smaller mass.

  
  


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  Gamma rays are high-energy electromagnetic waves, not particles, and carry no charge. Because they have no electric charge, they are not deflected by electric or magnetic fields.

  
  

This is why in experiments using cathode ray tubes or radioactive sources, gamma rays continue in a straight path, while alpha and beta rays bend under the influence of the fields.

Understanding this behavior is important in nuclear physics, radiation detection, and medical applications. For example, gamma rays can penetrate matter easily and are used in medical imaging and cancer treatment, whereas alpha and beta particles are stopped by thin layers of material.

In summary, the only radiation among the three that is not deflected by electric or magnetic fields is gamma rays, because they are neutral electromagnetic waves rather than charged particles.