λ = h/p
where:
* λ is the wavelength
* h is Planck's constant (6.626 x 10⁻³⁴ J⋅s)
* p is the momentum of the particle
Momentum (p) is given by:
p = mv
where:
* m is the mass of the particle
* v is the velocity of the particle
If the velocity of the particle is reduced by half, the momentum will also be reduced by half (since p is directly proportional to v).
Therefore, the wavelength associated with the moving particle will double.
This is because the wavelength is inversely proportional to momentum. If the momentum is halved, the wavelength will be doubled.