Radiation Safety Practice Exam

What charge does a beta particle possess?

1. +1 (positive one) charge

2. 0 (neutral) charge

3. -1 (negative one) charge

4. +2 (positive two) charge

The correct answer is: -1 (negative one) charge

A beta particle is a type of subatomic particle that is emitted during radioactive decay. Specifically, there are two types of beta particles: beta-minus (β-) and beta-plus (β+). The beta-minus particle, which is the more common type encountered in radiation safety contexts, carries a negative charge. This negative charge is due to the presence of an electron that is emitted from a nucleus when a neutron is converted into a proton and an electron, with the electron being expelled as a beta particle. The charge of -1 indicates that beta particles have the same charge as electrons. This is key in radiation safety considerations, as it influences how beta particles interact with materials and biological tissues. The negative charge makes beta particles react with other charged particles and electromagnetic fields, affecting their energy loss and penetration abilities. Therefore, when discussing the charge of a beta particle in the context of radiation safety, acknowledging that it carries a charge of -1 is fundamental for understanding its behavior and the potential risks associated with exposure to beta radiation.