In order to determine which option represents a beta particle, we need to understand the different types of particles mentioned:
1. Beta Particle: A beta particle is an electron or positron that is emitted from a nucleus during radioactive decay. When a beta particle is an electron, it is denoted in nuclear notation as [tex]${ }_{-1}^0 e$[/tex]. This notation signifies a particle with a mass number (top number) of 0 and an atomic number (bottom number) of -1.
2. Alpha Particle ([tex]$\alpha$[/tex]): An alpha particle is a helium nucleus, which consists of two protons and two neutrons. Its nuclear notation is typically [tex]${ }_2^4 He$[/tex], showing a mass number of 4 and an atomic number of 2.
3. Gamma Ray ([tex]$\gamma$[/tex]): Gamma rays are high-energy electromagnetic waves emitted from a nucleus. They do not have mass or charge and are represented by the Greek letter gamma ([tex]$\gamma$[/tex]).
4. Helium-4 ([tex]${ }_2^4 He$[/tex]): This is the same as the alpha particle, consisting of two protons and two neutrons. Its notation is [tex]${ }_2^4 He$[/tex].
Given these definitions, we can see which option correctly represents a beta particle:
- Option A: [tex]${ }_{-1}^0 e$[/tex] – This matches the nuclear notation for a beta particle (electron).
- Option B: [tex]$\alpha$[/tex] – This represents an alpha particle, not a beta particle.
- Option C: [tex]$\gamma$[/tex] – This represents a gamma ray, not a beta particle.
- Option D: [tex]${ }_2^4 He$[/tex] – This represents a helium-4 nucleus, which is an alpha particle, not a beta particle.
Therefore, the correct option that represents a beta particle is:
Option A: [tex]${ }_{-1}^0 e$[/tex]
