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QJEEM23Ph32a2: JEE Main 2023 Physics - Class 12 JEEM23Ph32a2 Solution: In Young's double slits experiment, the position of 5 bright…

In Young's double slits experiment, the position of 5 th\mathrm{^{th}} bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is :

Multiple Choice Options

  • A 60 μ\mu m
  • B 48 μ\mu m
  • C 36 μ\mu m
  • D 12 μ\mu m

Step-by-Step Verified Solution

In Young's double-slit experiment, the distance between the slits and the screen, L=1 mL = 1 \text{ m} , the wavelength of the light, λ=600 nm=600×10−9 m\lambda = 600 \text{ nm} = 600 \times 10^{-9} \text{ m} , and the position of the 5th bright fringe from the central maximum, y=5 cm=0.05 my = 5 \text{ cm} = 0.05 \text{ m} .

The distance between the central maximum and the nn th bright fringe is given by the formula:

yn=nλLdy_n = \frac{n\lambda L}{d}

where dd is the distance between the two slits.

We can rearrange this formula to solve for dd :

d=nλLynd = \frac{n\lambda L}{y_n}

Substituting the values given in the question, we get:

d=5×600×10−9×1×1005d = \frac{5 \times 600 \times 10^{-9} \times 1 \times 100}{5}

d=6×10−5 md = 6 \times 10^{-5} \text{ m}

d=60 μmd = 60 \ \mu\text{m}

Therefore, the separation between the slits is 60 μm60 \ \mu\text{m} .

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