Dual Nature of Radiation and Matter - Result Question 8

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8. If the kinetic energy of the particle is increased to 16 times its previous value, the percentage change in the de-Broglie wavelength of the particle is :

======= ####8. If the kinetic energy of the particle is increased to 16 times its previous value, the percentage change in the de-Broglie wavelength of the particle is :

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/dual-nature-of-radiation-and-matter/dual-nature-of-radiation-and-matter—result-question-8.md (a) 25

(b) 75

(c) 60

(d) 50

[2014]

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Answer:

Correct Answer: 8. (b)

Solution:

(b) As we know

$\lambda=\frac{h}{P}=\frac{h}{\sqrt{2 mK}} \quad(\because P=\sqrt{2 mKE})$ or $\frac{\lambda_1}{\lambda_2}=\sqrt{\frac{K_2}{K_1}}=\sqrt{\frac{16 K}{K}}=\frac{4}{1}$

Therefore the percentage change in de-Broglie

wavelength $=\frac{1-4}{4} \times 100=-75 %$