Question

In a Young's double slit experiment with wavelength $5890\dot{A}$, there are 60 fringes in the field of vision How many fringes will be observed in the same field of vision if wavelength used is $5460\dot{A}$?

• A. 65
• B. 60
• C. 55
• D. 50

Answer 1

The correct option is A 65

$n_1{\lambda }_1=n_2{\lambda }_2$
$60\times 5890=n_{2}5460$
$n_2=65$