IntroductionClassical physics is the basis of all physics which says that matter and energy are two distinct concepts according to Newton's law and the theory of electromagnetic radiation. Classical physics is centered on these assumptions, the position and momentum of particles can be calculated at any instant as they follow a trajectory, the energy of a particle can assume any arbitrary value, and the waves and particles are distinct concepts. However, classical physics failed to explain these hypotheses on the atomic scale, because these hypotheses formulated on the macro scale caused big problems in the late 19th century. However, problems in classical physics can be solved by modern mechanics known as quantum mechanics. [1, 2] Black Body Radiation When a black object has a temperature above zero, Kelvin does not emit light at all wavelengths, but it does emit a specific light called black body radiation. Hot objects emit electromagnetic radiation when atoms vibrate and electrons move. The black body spectrum is temperature dependent, meaning that as the temperature increases, electrons move faster, so more radiation comes from the black body. Classical physics fails to explain the shape of the black body spectrum. [3]Classical physics suggests that as frequency increases, energy density approaches infinity, but in fact, as frequency increases, density tends to decrease. The black body spectrum shows the peak wavelength and leans towards the short wavelength, so at high frequency it shows a short wavelength. [4]Max Planck introduced Plank's constant to describe that electromagnetic radiation is emitted in quanta. When an atom absorbs a specific energy, an electron goes into the excited state and then moves to the lower energy level releasing energy. M...... middle of paper ......m particle. [9]ConclusionTo conclude, classical mechanics and quantum mechanics have many similarities as well as differences. Classical mechanics solves the problem of systems on the macroscopic scale while quantum mechanics solves the same problem on the microscopic scale. On the atomic/microscopic scale, energy is quantized, meaning it cannot vary continuously, only in quanta. This suggests that it is impossible to find the position and momentum of a particle at any time on the atomic scale. Furthermore, this proves that particles cannot adopt any arbitrary values. It is worth mentioning that quantum mechanics uses Planck's constant in all the above equations to give a solution to the problem posed by classical physics. Planck's constant is very small and only makes a difference to about 34th decimal place, but it gives an accurate result and not an average as Newton's law suggests..