The kinetic energy of an electron is $4.55 \times 10^{-25} \ J$ and its mass is $9.1 \times 10^{-31} \ kg$. Calculate the velocity,momentum,and wavelength of the electron.

Given: $KE = 4.55 \times 10^{-25} \ J$,$m = 9.1 \times 10^{-31} \ kg$.
$1$. Velocity $(v)$:
$KE = \frac{1}{2} mv^2$
$4.55 \times 10^{-25} = \frac{1}{2} \times 9.1 \times 10^{-31} \times v^2$
$v^2 = \frac{2 \times 4.55 \times 10^{-25}}{9.1 \times 10^{-31}} = 10^6$
$v = 10^3 \ m \ s^{-1}$.
$2$. Momentum $(p)$:
$p = mv = 9.1 \times 10^{-31} \ kg \times 10^3 \ m \ s^{-1} = 9.1 \times 10^{-28} \ kg \ m \ s^{-1}$.
$3$. Wavelength $(\lambda)$:
Using de Broglie equation,$\lambda = \frac{h}{p}$
$\lambda = \frac{6.626 \times 10^{-34} \ J \ s}{9.1 \times 10^{-28} \ kg \ m \ s^{-1}} \approx 7.28 \times 10^{-7} \ m$.