ExamBro
ExamBro
AP EAMCET · PHYSICS · Dual Nature of Matter

A photo sensitive metallic surface emits electrons when X-rays of wavelength \(\lambda\) fall on it. The de-Broglie wavelength of the emitted electrons is (Neglect the work function of the surface, \(m\) is mass of the electron, \(h\) is Planck's constant, \(c\) is the velocity of light)

  1. A \(\sqrt{\frac{2 m c}{h \lambda}}\)
  2. B \(\sqrt{\frac{h \lambda}{2 m c}}\)
  3. C \(\sqrt{\frac{ m c}{h \lambda}}\)
  4. D \(\sqrt{\frac{h \lambda}{ m c}}\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(\sqrt{\frac{h \lambda}{2 m c}}\)

Step-by-step Solution

Detailed explanation

de-Broglie wavelength \(\lambda_0=\frac{h}{p}=\frac{h}{\sqrt{2 m E_k}}\) And \(E_K=h v=\frac{h c}{\lambda}\) \(\therefore \quad \lambda_v=\frac{h}{\sqrt{2 m \times \frac{h c}{\lambda}}}=\sqrt{\frac{\lambda h}{2 m c}}\)