Related InterviewSolutions

• The resolving power of a telescope can be increased by: A. increasing the objective focal length and decreasing the eyepiece focal length B. increasing the lens diameters C. decreasing the lens diameters D. inserting a correction lens between objective and eyepiece E. none of the above
• One of the two slits in a Young’s experiment is painted over so that it transmits only one-half the intensity of the other slit. As a result: A. the fringe system disappears B. the bright fringes get brighter and the dark ones get darker C. the fringes just get dimmer D. the dark fringes just get brighter E. the dark fringes get brighter and the bright ones get darker
• A liquid of refractive index n = 4/3 replaces the air between a fixed wedge formed from two glass plates as shown. As a result, the spacing between adjacent dark bands in the interference pattern:A. increases by a factor of 4/3 B. increases by a factor of 3 C. remains the same D. decreases to 3/4 of its original value E. decreases to 1/3 of its original value
• If white light is incident on a diffraction grating: A. the first order lines for all visible wavelengths occur at smaller diffraction angles than any of the second order lines B. some first order lines overlap the second order lines if the ruling separation is small but do not if it is large C. some first order lines overlap second order lines if the ruling separation is large but do not if it is small D. some first order lines overlap second order lines no matter what the ruling separation E. first and second order lines have the same range of diffraction angles 
• Two nearly equal wavelengths of light are incident on an N-slit grating. The two wavelengths are not resolvable. When N is increased they become resolvable. This is because: A. more light gets through the grating B. the lines get more intense C. the entire pattern spreads out D. there are more orders present E. the lines become more narrow 
• Monochromatic light is normally incident on a diffraction grating. The mth order line is at a diffraction angle θ and has width w. A wide single slit is now placed in front of the grating and its width is then slowly reduced. As a result: A. both θ and w increase B. both θ and w decrease C. θ remains the same and w increases D. θ remains the same and w decreases E. θ decreases and w increases
• A mixture of 450-nm and 900-nm light is incident on a diffraction grating. Which of the following is true? A. all lines of the 900-nm light coincide with even order lines of the 450-nm light B. all lines of the 450-nm light coincide with even order lines of the 900-nm light C. all lines of the 900-nm light coincide with odd order lines of the 450-nm light D. None of the lines of the 450-nm light coincide with lines of the 900-nm light E. All of the lines of the 450-nm light coincide with lines of the 900-nm light
• A light beam incident on a diffraction grating consists of waves with two different wavelengths. The separation of the two first order lines is great if: A. the dispersion is great B. the resolution is great C. the dispersion is small D. the resolution is small E. none of the above (line separation does not depend on either dispersion or resolution)
• Which of the following is true for Bragg diffraction but not for diffraction from a grating? A. Two different wavelengths may be used B. For a given wavelength, a maximum may exist in several directions C. Long waves are deviated more than short ones D. There is only one grating spacing E. Maximum occur only for particular angles of incidence
• As more slits with the same spacing are added to a diffraction grating the lines: A. spread farther apart B. move closer together C. become wider D. becomes narrower E. do not change in position or width