Question

What should be the velocity of an electron so that its momentum, becomes equal to that of a photon of wavelength $\text{1}00\mu \text{A}$ ?

• A. 700 m/s
• B. 1000m/s
• C. 1400 m/s
• D. 2800 m/s

Answer 1

Answer: (C)

Momentum $\frac{3}{2}\text{m}/\text{s}$ $\frac{2}{3}\text{m}/\text{s}$ ${\lambda }_0,$ $\frac{25}{16}{\lambda }_0$ $\frac{27}{20}{\lambda }_0$ $\frac{20}{27}{\lambda }_0$