Electromagnetic propulsion provides a non-contact way for delivering goods. The projectile typically does not contain explosives, which has apparent advantages over traditional methods. Due to the multi-physics nature, simulation is expensive and time-consuming. We established a simplified model in time domain incorporating mechanics and electromagnetics to study electromagnetic propulsion. Results show that important physical parameters such as force, velocity, acceleration, etc. can be extracted from the model without time-consuming efforts. We hope this model could help the exploration of electromagnetic propulsion.