Is presented the dynamics and kinematics of the semi-leptonic decays with interaction V-A calculating the decay width and the fraction of decay for each process using spectator model. The results are compared with the experimental data of the table particle data group, which show that the model prediction for this type of decay can be considered as a first approximation. This type of analysis is particularly important because it allows one hand, introduce to the beginner students to the study of particle physics and on the other gives the possibility to use strategies to address topics modern in physics courses at university level.