Question

The de-Broglie wavelength associated with a ball of mass $1\, kg$ having kinetic energy $0.5\, J$ is

• A. $6.626 \times 10^{-34} m $
• B. $13.20 \times 10^{-34} m$
• C. $10.38 \times 10^{-29} m$
• D. $6.626 \times 10^{-34}\, \mathring{A}$

Answer 1

Answer: (A)

$\lambda=\frac{ h }{ mv }=\frac{ h }{\sqrt{2 mE }}$
$=\frac{6.6 \times 10^{-34}}{\sqrt{2 \times 1 \times 0.5}}$
$=6.6 \times 10^{-34} m$