A slit of width $$a$$ is illuminated by red light of wavelength $$6500 \mathop A\limits^o$$. If the first diffraction minimum falls at $$30^{\circ}$$, then the value of $$a$$ is
Which of the following statements are correct with reference to single slit diffraction pattern?
(I) Fringes are of unequal width.
(II) Fringes are of equal width.
(III) Light energy is conserved.
(IV) Intensities of all bright fringes are equal.
In the Young's double slit experiment a monochromatic source of wavelength $$\lambda$$ is used. The intensity of light passing through each slit is $$I_0$$. The intensity of light reaching the screen $$S_C$$ at a point $$P$$, a distance $$x$$ from $$O$$ is given by (Take, $$d<< D$$)
The work-function of a metal is 1 eV. Light of wavelength $$3000 \mathop A\limits^o$$ is incident on this metal surface. The velocity of emitted photoelectrons will be