In an inelastic collision, two bodies with masses $ m_1 = 1\, \text{kg} $ and $ m_2 = 3\, \text{kg} $ collide. Their initial velocities are $ u_1 = 2\, \text{m/s} $ and $ u_2 = 0\, \text{m/s} $, respectively. What is the change in kinetic energy ($ \Delta K $)?