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Wave/particle duality

Q2.

(a) Electrons behave in two distinct ways. This is referred to as the duality of electrons.

(i) State what is meant by the duality of electrons.

Duality of electrons means that electrons behave as both particles and waves

(ii) Give one example of each type of behaviour of electrons.

particle behaviour: deflection of electrons in an electromagnetic field

wave behaviour: electron diffraction

(3 marks)

(b) Calculate the speed of electrons that have a de Broglie wavelength of 1.70 × 10–10 m.

λ dB= h/p = h/mv

v = h/mλ dB

v = 6.63 x 10-34/(9.11 × 10–31 x 1.70 × 10–10)

v = 4.28 × 106 m s–1

(2 marks)

(Total 5 marks)