Home › MCQs › EEJ MAIN Chemistry › Question #7175
Back to Questions
EEJ MAIN Chemistry QUESTION #7175
Question 1
According to the de Broglie hypothesis, if the velocity of a particle is tripled and its mass is doubled, how does the associated wavelength change?
  • Decreases by a factor of 6✔️
  • Increases by a factor of 6
  • Decreases by a factor of 1.5
  • Remains the same
Correct Answer Explanation
The de Broglie wavelength is given by $\lambda = \frac{h}{mv}$.
  • Initial wavelength: $\lambda_{1} = \frac{h}{mv}$
  • New mass $m' = 2m$, New velocity $v' = 3v$
  • New wavelength: $\lambda_{2} = \frac{h}{(2m)(3v)} = \frac{h}{6mv}$
  • Therefore, $\lambda_{2} = \frac{\lambda_{1}}{6}$