To calculate the de-Broglie wavelength of a particle, we use the formula:λ=mvhwhere λ is the wavelength, h is Planck's constant, m is the mass of the particle, and v is the velocity of the particle.Given:Mass m=1mg=1×10−3g=1×10−6kgVelocity v=10m/sPlanck's constant h=6.63×10−34JsSubstitute these values into the formula:λ=1×10−6×106.63×10−34=10−56.63×10−34=6.63×10−29mTherefore, the de-Broglie wavelength of the particle is 6.63×10−29m.