The equation which is meaningful only for sub microscopic particles, such as electrons and atoms, and not for macroscopic objects should be explained using the concept of De Broglie’s hypothesis.
De Broglie’s hypothesis explains the behaviour of waves. Waves behave like particles whereas particles can behave like wave. De Broglie derived the equation in which the particle and wave properties are related:
where, - the wavelength associated with a moving particle; h- Planck’s constant; m- the mass of the particle and u - the velocity of the moving particle.