AP EAMCET20228 Jul 2022Evening ShiftPhysicsWave OpticsActual
In a young's double slit experiment, the slits are separated by 0.28 ~mm and the screen is placed 1.4 ~m away from the slits. The distance between the central bright fringe and the 4 th order bright fringe is measured to be 1.2 ~cm . The wavelength of light used in this experiment is
Options
- A2400 ~nm
- B600 ~nm
- C1200 ~nm
- D800 ~nm
Correct answer
B. 600 ~nm
Step-by-step solution
Distance between the slits, d=0.28 ~mm =0.28 10⁻³ ~m Distance between the slits and the screen, D=1.4 ~m Distance between the central fringe and the fourth (n=4) fringe, u=1.2 ~cm =1.2 10⁻² ~m In case of a constructive interference, we have the relation for the distance between the two fringes as: u=n D d Where, aligned & n= Order of fringes =4 & = Wavelength of light used & = u d n D & = 1.2 10⁻² 0.28 10⁻³ 4 1.4 & =6 10⁻⁷ & =600 ~nm aligned Hence, the wavelength of the light is 600 ~nm .