HSSC Senior Scientific Assistant/Dt.-31-12-2022 Morning Shift (Cat. No.-3,4,9)

Total Questions: 100

31. When X-rays emitted from molybdenum are allowed to pass through a zirconium filter, which of the following occurs?

Correct Answer: (b) It absorbs radiation of longer wavelength

32. The ballistic coefficient of a projectile is where, M = Mass of projectile, Cd = Coefficient of drag, A = Cross-sectional area of projectile

Correct Answer: (a) M / CdA

33. The angle of rifling (θ), pitch of rifling (l), and calibre of rifle (d) are connected by which of the following relations?

Correct Answer: (a) d = l / (π * tan θ)

34. In recoil-operated firearms like a pistol, the automatic mechanism works because of

Correct Answer: (d) force of recoil acting on walls and neck of cartridge case

35. The range of fire can be determined by

Correct Answer: (c) the dispersion pellet

36. Exit wound of gunshot injury contains

Correct Answer: (d) None of the above

37. For wound ballistics study in human beings, which of the following is used in experiments?

Correct Answer: (b) 20% gelatin gel block

38. In paper chromatography, if a = distance travelled by the component and b = distance travelled by the solvent, then the retention factor value is-

Correct Answer: (a) a / (2b)

39. In Reverse Phase Chromatography (RPC), the stationary phase is-

Correct Answer: (b) non-polar

40. The separation technique involving the movement of charged particles through a matrix under the influence of an applied electric field is called:

Correct Answer: (a) Electrophoresis