Question

Two coherent sources of wavelength $6.2\times 10m$ produce interference. The path difference corresponding to $10th$ order maximum will be

• A. $6.2\times {10}^{-6}m$
• B. $3.1\times {10}^{-6}m$
• C. $1.5\times {10}^{-6}m$
• D. $12.4\times {10}^{-6}m$

Answer 1

The correct option is B $3.1\times {10}^{-6}m$

$\text{Given:-}$ $\lambda =6.2\times {10}^{-7}m$

$\text{Solution:-}$ We know that,

path difference $=\frac{\lambda }{2\lambda }\left(phasedifference\right)$

$=\frac{\lambda }{2\lambda }\left(n\lambda \right)=\frac{n\lambda }{2}$

$\lambda =6.2\times {10}^{-7}m$

So path difference of$(n+1^{th}and{n}^{th}orderismaximumisby\frac{n\lambda }{2})$

$\Rightarrow \Delta =\frac{10\times \lambda }{2}=\frac{6.2\times {10}^{-7}\times 10}{2}$

$\therefore \Delta =3.1\times {10}^{-6}m$

$\text{Hence the correct option is B}$