3 Ionising radiations are emitted by unstable nuclei: (a) (i) Which particle has the same mass as but opposite charge to a $eta^-$ particle? Put a cross (X) in the box next to your answer - Edexcel - GCSE Physics - Question 3 - 2013 - Paper 1

A beta particle will travel further in air than an alpha particle due to several factors:

1. Mass: The beta particle (which is an electron) has a much smaller mass compared to an alpha particle (which is composed of two protons and two neutrons). This lower mass results in less interaction with air molecules, allowing beta particles to penetrate the air more effectively.

2. Charge: Alpha particles are positively charged and interact more strongly with matter due to their larger mass and charge. This results in increased ionization of air molecules, which slows them down and reduces their range. In contrast, beta particles encounter less resistance and can travel further before being absorbed.

Following the radioactive decay of a nucleus, the nucleus might undergo some rearrangement, losing energy as gamma radiation. Gamma radiation is a form of high-energy electromagnetic radiation that emits during the decay process, allowing the nucleus to drop to a lower energy state.