8 Two particles, \(A\) and \(B\), are travelling towards each other along a straight horizontal line.
Particle \(A\) has velocity \(2 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) and mass \(m \mathrm {~kg}\).
Particle \(B\) has velocity \(- 2 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) and mass 3 kg .
\includegraphics[max width=\textwidth, alt={}, center]{a381686b-0b1e-41ba-b88f-be1601e42098-5_220_1157_516_440} The particles collide.

1. If the particles move in opposite directions after the collision, each with speed \(0.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }\), find the value of \(m\).
2. If the particles coalesce during the collision, forming a single particle which moves with speed \(0.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }\), find the two possible values of \(m\).