OnlineCBT
Chemistry · Structure of atom
हिन्दीCalculate the kinetic energy (in J) of an electron whose de Broglie wavelength is \( 1.0 \times 10^{-10} \text{ m} \) (\( m = 9.1 \times 10^{-31} \text{ kg} \), \( h = 6.626 \times 10^{-34} \text{ J s} \)).
Correct answer · Option 1
\( 2.4 \times 10^{-18} \text{ J} \)
Explanation
Using \( \lambda = \frac{h}{\sqrt{2m \cdot \text{K.E.}}} \), squaring and solving for K.E. gives \( \text{K.E.} = \frac{h^2}{2m\lambda^2} = \frac{(6.626 \times 10^{-34})^2}{2 \times 9.1 \times 10^{-31} \times (10^{-10})^2} \approx 2.4 \times 10^{-18} \text{ J} \).
