Wave Optics Tes...

The fractional change in intensity of the central maximum as function of time is

When the source comes toward the point $$Q$$,

Find the fringe width of the fringe pattern.

Calculate the number of fringes.

A point source is emitting light of wavelength 6000 $$\overset{o}{A}$$ is placed at a very small height h above a flat reflecting surface $$MN$$ as shown in the figure. The intensity of the reflected light is $$36$$% of the incident intensity. Inference fringes are observed on a screen placed parallel to the reflecting surface at a very large distance $$D$$ from it. If the intensity at $$p$$ be maximum, then the minimum distance through which the reflecting surface $$MN$$ should be displaced so that at $$P$$ again becomes maximum?

A distant star which is moving away with a velocity of $$ 10^6$$ m/sec is emitting red line of frequency$$4.5\times 10^14 $$ Hz. The observed frequency of this spectral line is

Assuming human pupil to have a radius of 0.25 cm and a comfortable viewing distance of 25cm, the minimum separation between two objects that human eye can resolve at 500 nm wavelength is :

Two identical coherent sources are placed on a diameter of a circle of radius R at a separation d (d << R, d >> $$\lambda$$) symmetrically about the centre of the circle. The sources emit identical wavelength $$\lambda$$. The number of the points on the circle with maximum intensity is

Light is incident at an angle $$\displaystyle \phi $$ with the normal to a plane containing two slits of separation d Select the expression that correctly describe the positions of the interference maxima in terms of the incoming angle $$\displaystyle \theta $$ and outgoing $$\displaystyle \phi $$

A paper, with two marks having separation d, is held normal to the line of sight of an observer at a distance of 50m. The diameter of the eye-lens of the observer is 2 mm. Which of the following is the least value of d, so that the marks can be seen as separate? (The mean wavelength of visible light may be taken as 5000 $$A^o$$)