Assertion: In Young's double slit experiment, | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) In Young's double slit experiment,the fringe width is given by $\beta = \frac{\lambda D}{d}$.The number of bright fringes $N$ that can be observed

Vedclass · Accepted Answer

If both the Assertion and Reason are incorrect.

Vedclass · Answer

(D) In Young's double slit experiment,the fringe width is given by $\beta = \frac{\lambda D}{d}$.The number of bright fringes $N$ that can be observed on a screen of width $W$ is given by $N = \frac{W}{\beta} = \frac{Wd}{\lambda D}$.From this relation,it is clear that the number of fringes $N$ is inversely proportional to the wavelength $\lambda$ $(N \propto \frac{1}{\lambda})$.If the wavelength $\lambda$ is doubled,the number of fringes $N$ will be halved,meaning it decreases.Therefore,the Assertion is incorrect because the number of fringes decreases,not increases.The Reason is also incorrect because the number of fringes is inversely proportional to the wavelength,not directly proportional.Thus,both the Assertion and the Reason are incorrect.

Assertion: In Young's double slit experiment,if the wavelength of incident monochromatic light is doubled,the number of bright fringes on the screen will increase.
Reason: The maximum number of bright fringes on the screen is directly proportional to the wavelength of light used.

Similar Questions

In Young's double slit experiment,how many maximas can be obtained on a screen (including the central maximum) on both sides of the central fringe if $\lambda = 2000\,{\mathring A}$ and $d = 7000\,{\mathring A}$?

In a Young's double slit experiment, a small detector measures an intensity of illumination of $I$ units at the centre of the fringe pattern. If one of the two (identical) slits is now covered, the measured intensity will be

In a Young's double slit experiment,light of $500 \ nm$ is used to produce an interference pattern. When the distance between the slits is $0.05 \ mm$,the angular width (in degrees) of the fringes formed on the distant screen is close to $........^o$.

The correct curve between fringe width $\beta$ and the distance between the slits $(d)$ is:

In a double slit experiment shown in the figure,when light of wavelength $400 \ nm$ is used,a dark fringe is observed at $P$. If $D=0.2 \ m$,the minimum distance between the slits $S_1$ and $S_2$ is . . . . . . $mm$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module

Assertion: In Young's double slit experiment,if the wavelength of incident monochromatic light is doubled,the number of bright fringes on the screen will increase.Reason: The maximum number of bright fringes on the screen is directly proportional to the wavelength of light used.