If a diffraction grating is placed in the path of a light beam it reveals______________?

Related Mcqs:

1. A diffraction grating has 500 lines per mm. Its slit spacing or grating element will be equal to ____________________?

   A. 500 mm
   B. 5 x 10-3 mm
   C. 2 x 10-5 mm
   D. 2 x 10-3 mm

2. X-rays are diffracted by a crystal but not by a diffraction grating because_____________?

   A. The ions in a crystal are well arranged
   B. The lines in a diffraction grating cannot reflect X-rays.
   C. The penetration power of X-rays is high in a diffraction grating
   D. The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal

3. A body moving along the circumference of a circle completes two revolutions. If the radius of the circular path is R the ration of displacement to the covered path will be_____________?

   A. πR
   B. 2π R
   C. 0
   D. 4πR

4. Moving along the circumference of a circle completes two revolutions. If the radius of the circular path is R, the ratio of displacement to the covered path will be_______________?

   A. πR
   B. 2πR
   C. 0
   D. 4πR

5. When light incident normally on thin film the path difference depends upon ________________?

   A. thickness of the film only
   B. nature of the film only
   C. angle of indidence only
   D. all thickness nature and angle of incidence

6. Wavelength of X-rays falling at glancing angle of 30? on a crystal with atmic spacing 2 x 10-10 for the fist order diffraction is________________?

   A. 4 x 10-10 m
   B. 2 x 10-10 m
   C. 0.02×10-10m
   D. 20×10-10m

7. Diffraction effect is____________________?

   A. more for a round edge
   B. less for a round edge
   C. more for a sharp edge
   D. less for a sharp edge

8. Diffraction fringes are____________________?

   A. equally spaced
   B. distance between them increases
   C. distance between then decreases
   D. they are adjacent with no space in between

9. A point source of light placed in a homogeneous medium gives rise to ___________________?

   A. a cylindrical wave front
   B. an elliptical wave front
   C. a spherical wave front
   D. a plane wave front

10. In a photoelectric effect monochromatic light is incident on a metal surface. If the incident light of twice the intensity but of same wavelength the kinetic energy of the emitted electron_______________?

    A. Becomes double
    B. Remains same
    C. Becomes half
    D. First increases then decrease because of the curvilinear graph