51. Which of the following is true for metals?
52. If the drift velocity of holes under a field gradient of 150 V/m is 7.5 m/s, their mobility (in SI units) is
53. In a powder diffraction photograph of copper (fcc structure with a lattice parameter of 0.3608 nm) taken with a cu-ka radiation (? = 0.154 nm), the Bragg angle for the first line is
54. The lowest angle reflection in a powder diffraction experiment or an fcc metal using Cu-Ka radiation (y = 1.54°A) occured at an angle of 19°30'. The lattice parameter of the metal is . . . . . . . . °A.
55. Match the phenomenon with their specific effects on X-ray diffraction patterns
P. Macroscopic residual stress
1. Additional diffraction lines
Q. Microscopic residual stress
2. X-ray line shift
R. Ordering reaction
3. Debye rings of non-uniform intensity
S. Preferred orientation
4. X-ray line broadening
| P. Macroscopic residual stress | 1. Additional diffraction lines |
| Q. Microscopic residual stress | 2. X-ray line shift |
| R. Ordering reaction | 3. Debye rings of non-uniform intensity |
| S. Preferred orientation | 4. X-ray line broadening |