Question 57

Dual behaviour of matter proposed by de Broglie led to the discovery of electron microscope often used for the highly magnified images of biological molecules and other type of material. If the velocity of the electron in this microscope is 1.6 × 10^{6} ms^{–1}, calculate de Broglie wavelength associated with this electron.

Answer

From de Broglie’s equation,

λ = *h/mv*

Substituting the values in this equation,we get

6.626x 10^{-34} **/** (9.11x10^{-31})(1.6x10^{6})

= 4.55 x 10^{-10}m

= 455pm

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