Matter Waves Of Macroscopic Objects

The de Broglie relation $\lambda =\frac{h}{mv}$, given in NCERT, applies to all matter, including everyday objects. For the cricket ball, momentum is $p=mv=0.15\times 40=6.0$ kg·m/s. Substituting into the relation gives $\lambda =\frac{6.63\times 10^{-34}}{6.0}=1.1\times 10^{-34}$ m. This wavelength is fantastically smaller than any nucleus, which is precisely why the wave nature of macroscopic objects is utterly unobservable and everyday objects appear purely particle-like. The value $1.1\times 10^{-32}$ m is wrong because it misplaces the exponent by two orders during the division. The value $6.6\times 10^{-34}$ m is wrong because it uses Planck's constant without dividing by the momentum of 6.0 kg·m/s. The value $1.1\times 10^{-24}$ m is wrong because it is ten orders of magnitude too large, an arithmetic error in the exponent. As stated in NCERT Class 12, Chapter 11, matter waves are significant only for very light particles like electrons, since large masses give immeasurably tiny wavelengths. This result illustrates the correspondence principle: quantum wave effects become utterly negligible for large masses, so classical mechanics accurately describes everyday motion. The de Broglie wavelength becomes experimentally accessible only for extremely light particles such as electrons, neutrons, or atoms moving slowly. A magnitude check confirms that a wavelength around $10^{-34}$ m is vastly below any measurable scale, explaining why we never see a cricket ball diffract.