Exams › JEE Advanced › Physics

In Young's double-slit experiment, the ratio of intensity at bright fringes to dark fringes is 9. Which of the following statements is/are correct? (A) The intensities at the screen from the two slits are 5 units and 4 units respectively. (B) The intensities at the screen from the two slits are 4 units and 1 unit respectively. (C) The amplitude ratio is 6. (D) The amplitude ratio is 2.

1. The intensities from the two slits are 5 units and 4 units respectively
2. The intensities from the two slits are 4 units and 1 unit respectively
3. The amplitude ratio is 6
4. The amplitude ratio is 2

Correct answer: The intensities from the two slits are 4 units and 1 unit respectively

Solution

From the intensity ratio condition, we find the amplitude ratio A1/A2 = 2, meaning I1:I2 = 4:1. This matches option B (4 units and 1 unit) and option D (amplitude ratio is 2). Both B and D are correct.

Related JEE Advanced Physics questions

• What factor influences the visibility of fringes in an interference pattern?
• When the screen is moved further along the x-axis away from the source, which of the following statements is false?
• In the Young's double slit experiment using a monochromatic light of wavelength λ, the path difference (in terms of an integer n) corresponding to any point having half the peak intensity is
• Using the expression 2d sin θ = λ, one calculates the values of d by measuring the corresponding angles θ in the range 0 to 90°. The wavelength λ is exactly known and the error in θ is constant for all values of θ. As θ increases from 0°:
• Two coherent point sources separated by a distance d = 5 micrometers emit light of wavelength lambda = 2 micrometers in phase. A circular wire of radius R = 20 micrometers is placed symmetrically around the two sources (sources lie along a diameter). Points A and B are at the ends of the diameter along the line joining the sources; points C and D are at the ends of the diameter perpendicular to the line joining the sources. Which of the following is correct?
• Young's double slit experiment is performed in a medium of refractive index mu1 = 4/3. A thin transparent slab of refractive index mu2 = 3/2 and thickness t = 8 micrometers is placed in front of slit S2. The magnitude of the optical path difference (with respect to the liquid medium) at the central point O is:

⚔️ Practice JEE Advanced Physics free + battle 1v1 →