Question

The question has statement 1 and statement 2. Out of the four choices given after the statements, choose the one that best describes the two statements.
Statement 1: Davisson- Germer experiment established the wave nature of electrons.
Statement 2: If electrons have wave nature, they can interfere and show diffraction.
A. Statement -1 is false. Statement -2 is true.
B. Statement -1 is true. Statement -2 is false.
C. Statement -1 is true, statement -2 is true, statement -2 is correct explanation for statement -1
D. Statement -1 is true, statement -2 is true, statement -2 is not the correct explanation of statement -1.

Answer 1

Hint: Diffraction is a phenomenon exhibited by waves when it is made to pass through tiny apertures or obstacles. For diffraction to occur, the wavelength of the wave should be of the order of obstacle size.

Complete step by step answer:
Davisson- Germer experiment was a milestone in establishing the wave nature of particles as its electron diffraction pattern was seen with the help of this for the first time. The waves associated with electrons are de Broglie waves that have wavelength given by de Broglie relation (h/p). In an experimental setting, they used electrons from a gun that were accelerated first and then diffracted by nickel crystals which were collected with the help of a detector. The separation between two atomic planes was of the order of the wavelength of electron waves and hence fit for producing a diffraction pattern. The pattern formation was confirmed by checking the angular variation of electrons. In a particular direction, a peak was observed, which confirmed the interference maxima.
Therefore, the two statements given to us i.e., Davisson- Germer experiment established the wave nature of electrons and electrons show diffraction are correct. Also, statement 2 is the correct explanation of statement 1.

Therefore the correct answer is option (C).

Note:
The words diffraction and interference are used interchangeably often. In the question in statement 2, it is mentioned that electrons interfere and produce diffraction patterns. The point of the experiment is that we saw a peak of electrons in a particular direction which implies that waves of electrons are interfering constructively in a particular direction and interfering destructively in all other directions.