MCQ
In a biprism experiment using sodium light $\lambda = 6000\, Å$ an interference pattern is obtained in which $20$ fringes occupy $2\, cm$. On replacing sodium light by another source of wavelength $\lambda_2$ without making any other change $30$ fringes occupy $2.7\, cm$ on the screen. What is the value of $\lambda_2$?.......$\mathop A\limits^o $
  • A
    $4500$
  • $5400$
  • C
    $5600$
  • D
    $4200$

Answer

Correct option: B.
$5400$
b

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