So I was reading about De Broglie's theory of particle-wave duality the other day and I came across the equation: λ=h/p. I expect most of you are familiar with this equation but if you're not, it is: wavelength = Planck's length over momentum (mass x velocity). So I thought i'd try and find the Earth's wavelength. So first I found out what I would have to do to find p, which is (5.9742x1024kg * (approx) 3x104 m/s). So... 6.626x10-34/(5.9742x1024kg * (approx) 3x104 m/s) This is equal to... 3.697×10^-63 meters. When I first saw that, I was mind blown. Will someone explain why it's wavelength is that small? Thanks, Ben - i'm unsure of this because well, i'm quite young (15).