Direction:Answer the MCQ no.15 to 17 on the basis of the folowing paragraph:Wave property of electron implies that they will show diffraction effected . Davisson and Germer demonstrated this by diffracting electron from crystals . The law governing the diffraction from a crystals is obtained by requiring that electron waves reflected from the planes of atoms in a crystal interfere constructiely as shown in figure
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Electrons accelerated by potential V are diffracted from a crystal.Given that `h=6.62 xx 10^(-34) J s , e= 1.6 xx 10^(-19) C` and `m_e = 9.1 xx 10^(-31) kg.`.If `d= 1 overset @A` and `i= 30^@`,V should be about

Options

A. 50 V
B. 500 V
C. 1,000 V
D. 2,000 V