We all know that when the current flows through the conductor, there is a certain resistance due to the conductor, so the conductor will heat. and the heat is followed by this formula: q = 0.24i2rt; where q is heat generation, 0.24 is a constant, i is a current flowing through the conductor, r is the electrical resistance of the conductor, t is the time of current flowing through the conductor; according to this formula it is not difficult to see the simple working principle of the fuse.