We have tried to show the necessity to search for any existent classical solution to solve any physical problem before trying to use Quantum and Relativity. We have used this method to verify carefully some important events in Physics that the claimed inability of Classical Physics to explain them was the origin of advent of Modern Physics. Important phenomena currently regarded totally as supporters of Quantum and Relativity Physics's are justified in Classical Physics. These are: photoelectric effect, Compton effect (as a Doppler effect), Stertn-Gerlach experiment, Franck-Hertz experiment, wave-like behavior of electron beams, presentation of the electromagnetic theory without Special Relativity (and without breach of Newton's 3rd law), optical justification of deviation of stars light by Sun. Also correction of some serious shortcomings in them are presented, like: proving invalidity of the Planck's derivation of E=hν, justification of the Hall effect (without supposition of hole), verification of the concept of photon (pressure), proving that stellar aberration doesn't contradict ether drag, showing the invalidity of distinguishing between inertial and gravitational masses.