SATHEE: Optics 6 Question 19

Optics 6 Question 19

21. In a YDSE bi-chromatic light of wavelengths $400 n m$ and $560 n m$ are used. The distance between the slits is $0.1 m m$ and the distance between the plane of the slits and the screen is $1 m$ . The minimum distance between two successive regions of complete darkness is

(2004, 2M)

(a) $4 m m$

(b) $5.6 m m$

(d) $28 m m$

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Solution:

Let $n$ th minima of $400 n m$ coincides with $m$ th minima of $560 n m$ , then

$\begin{aligned} (2 n - 1) \frac{400}{2} & = (2 m - 1) \frac{560}{2} \\ or \frac{2 n - 1}{2 m - 1} & = \frac{7}{5} = \frac{14}{10} = \dots \end{aligned}$

i.e. 4th minima of $400 n m$ coincides with $3 r d$ minima of $560 n m$ .

Location of this minima is,

$\begin{aligned} Y_{1} & = \frac{(2 \times 4 - 1) (1000) (400 \times 10^{- 6})}{2 \times 0.1} \\ = 14 m m \end{aligned}$

Next 11th minima of $400 n m$ will coincide with 8th minima of $560 n m$ .

Location of this minima is,

$Y_{2} = \frac{(2 \times 11 - 1) (1000) (400 \times 10^{- 6})}{2 \times 0.1} = 42 m m$

$∴$ Required distance $= Y_{2} - Y_{1} = 28 m m$

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Optics 6 Question 19

21. In a YDSE bi-chromatic light of wavelengths $400 n m$ and $560 n m$ are used. The distance between the slits is $0.1 m m$ and the distance between the plane of the slits and the screen is $1 m$ . The minimum distance between two successive regions of complete darkness is

Solution:

इंजीनियरिंग की तैयारी

चिकित्सा तैयारी

एनसीईआरटी पुस्तकें और समाधान

महत्वपूर्ण संसाधन

अन्य संसाधन

पाठ्यक्रम

परीक्षा मंच

नमूना मॉक टेस्ट

सदस्यता

एनसीईआरटी व्यायाम वीडियो समाधान

Optics 6 Question 19

21. In a YDSE bi-chromatic light of wavelengths 400nm and 560nm are used. The distance between the slits is 0.1mm and the distance between the plane of the slits and the screen is 1m. The minimum distance between two successive regions of complete darkness is

Solution:

इंजीनियरिंग की तैयारी

चिकित्सा तैयारी

एनसीईआरटी पुस्तकें और समाधान

महत्वपूर्ण संसाधन

अन्य संसाधन

पाठ्यक्रम

परीक्षा मंच

नमूना मॉक टेस्ट

सदस्यता

एनसीईआरटी व्यायाम वीडियो समाधान

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21. In a YDSE bi-chromatic light of wavelengths $400 n m$ and $560 n m$ are used. The distance between the slits is $0.1 m m$ and the distance between the plane of the slits and the screen is $1 m$ . The minimum distance between two successive regions of complete darkness is