Question

The kinetic energy of a fast-moving particle of mass $1 \times 10^{-31}\text{ kg}$ is associated with a de Broglie wavelength $63\text{ nm}$ is ($h = 6.3 \times 10^{-34}\text{ Js}$)}

• A. $5 \times 10^{-21}\text{ J}$
• B. $1 \times 10^{-22}\text{ J}$
• C. $5 \times 10^{-22}\text{ J}$
• D. $1 \times 10^{-21}\text{ J}$

Hint:

Always keep track of powers of 10. For $h/\lambda$, notice that $6.3/63 = 0.1$, which makes the calculation much faster.

Answer 1

The Correct Option is C