A β+\beta^+β+ particle is a fast-moving positron.
Which statement explains how β+\beta^+β+ particles are emitted from an atom?
A proton changes into a neutron and a β+\beta^+β+ particle is emitted from the nucleus.
A neutron changes into a proton and a β+\beta^+β+ particle is emitted from the nucleus.
An electron in an inner shell is converted into a positron and is emitted from the atom.
A positron is ejected from an outer electron shell of the atom.
484 exam-style questions on CIE IGCSE Physics 5.2 Radioactivity, covering 5.2.1 Background radiation and measuring count rate, 5.2.2a Alpha, beta and gamma emission, 5.2.2b Deflection and ionising effects of nuclear radiation, 5.2.3a Radioactive decay, 5.2.3b Effects of decay on the nucleus and decay equations, 5.2.4a Half-life, 5.2.4b Choosing isotopes for applications, and 5.2.5 Effects of ionising radiation and safety precautions. Each one has a worked solution and a mark scheme showing where the marks go.