Here features our team’s physics-essay that really took us a long time to accomplish our goals. Following is the conclusion part which is written by me:
According to the research given above, the theory has been successfully drawn by us. First of all, we all get the point that because of induction, there will always has some voltage in the secondary coil, no matter there is a device connected to it. That is, alternated magnetic field could bring alternated electric current and vise versa. The principle, however, is that the current through the primary coil is able to produce a magnetic field. Because of the presence of the iron bar, the effect of the mutual inductance will be magnified. Thus, it restrain the self-inductance and more emf will be in the secondary coil. Ideally, the relationship between the voltage of the primary coil and that of the secondary coil depends on the ratio of number of turns. If the number of turns in the secondary coil is greater, it will called a step-up transformer, and it can improve the voltage and decrease the current from the primary circuit. But if the primary coil’s number of turns is greater, the transformer will be named a step-down transformer which means the voltage will be reduced and the current will be increased. But in fact, since the influence is caused by self-inductance, the impedance will diminish the voltage in the secondary coil because the magnetic flux is dissipated. Despite the transformer, as for the instance of the launch system of the coils, magnetic field is widely utilized. As the content says, alternated electric current will produce a magnetic field. Thus, the coil is made up to two poles, and the object to be thrust is magnetized. Because of the relatively strong repulsive force, the object will be exerted a huge amount of force to be accelerated, and the consequence is, obviously, it will be shoot and travel with high velocity.