The high-speed electron emitted from the nucleus is called?

• A. Alpha radiation
• B. Beta radiation
• C. Gamma radiation
• D. X-ray radiation

Answer: (B)

Beta radiation is the process where a nucleus emits a high-speed electron (a beta particle) during beta-minus decay. In this decay, a neutron is transformed into a proton, an electron, and an antineutrino; the newly formed proton remains in the nucleus, raising the atomic number by one, while the electron is ejected with kinetic energy. This distinguishes beta radiation from alpha radiation, which is a helium-4 nucleus emitted; gamma radiation, which are high-energy photons emitted from excited nuclear states, and X-rays, which are photons arising from electronic transitions rather than from the nucleus. The emitted high-speed electron specifically identifies beta-minus decay.