Answer
Velocity operator can be define as momentum operator divided by mass of partical.
Momentum operator can be given as
p^=ℏi∂∂x\hat{p}=\frac{\hbar}{i}\frac{\partial}{\partial x}p^=iℏ∂x∂
And velocity operator can be obtain as
v^=p^m=ℏim∂∂x\hat{v}=\frac{\hat{p}}{m}=\frac{\hbar}{im}\frac{\partial}{\partial x}v^=mp^=imℏ∂x∂