Answer
(a) $\lambda = 1.1\times 10^{-34}~m$
(b) $v = 1.7\times 10^{-23}~m/s$
Work Step by Step
(a) We can find the de Broglie wavelength:
$\lambda = \frac{h}{m~v}$
$\lambda = \frac{6.626\times 10^{-34}~J~s}{(0.200~kg)(30~m/s)}$
$\lambda = 1.1\times 10^{-34}~m$
(b) We can find the speed:
$\lambda = \frac{h}{m~v}$
$v = \frac{h}{m~\lambda}$
$v = \frac{6.626\times 10^{-34}~J~s}{(0.200~kg)(0.20\times 10^{-9}~m)}$
$v = 1.7\times 10^{-23}~m/s$
