Question

Figure below shows a version of Young’s Experiment performed by directing a beam of electrons on double slit. The screen reveals a pattern of bright and dark fringes similar to an interference as pattern produced when a beam of light is used.

1. Which property of electron is revealed in this observation?

2. If the electrons are accelerated by a p.d. of 54 V, what is the value of wavelength associated with electrons.

3. In similar experiment if the electron beam is replaced by bullets red form a gun, no interference pattern is observed. Give reason.

Answer 1

1. Dual nature or wave nature.

2. λ = \(\frac{12.27A^0}{\sqrt{V}}\)

= \(\frac{12.27}{\sqrt{54}}\) = 1.67 A⁰

3. λ = \(\frac{h}{mv}\) Since the mass of the bullet is very large compared to the mass of electron, the de Broglie wavelength is not considerable.