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

Total Questions: 100

21. In a frequency distribution, mid-value of a class is 15 and class interval is 4. The lower limit of the class is-

Correct Answer: (b) 13

22. Which of the following is a unique property of laser?

Correct Answer: (c) Coherence

23. Which of the following is not a characteristic of laser?

Correct Answer: (c) Divergent

24. The most powerful analytical technique(s) which offer(s) the possibility of chemical analysis is-

Correct Answer: (b) Infrared absorption spectroscopy

25. A body of mass m is projected with a speed u making an angle θ with the horizontal. The change in momentum suffered by the body along the Y-axis between the starting point and the highest point of its path will be-

Correct Answer: (b) mu sinθ

26. A bullet of mass 25 g moving with a velocity of 200 cm/s is stopped within 5 cm of the target. The average resistance offered by the target is-

Correct Answer: (b) 1 N

27. Water rises to a height of 16.3 cm in a capillary tube of height 18 cm above the water level. If the tube is cut at a height of 12 cm-

Correct Answer: (b) Water will stay at a height of 12 cm in the capillary tube

28. Bernoulli's equation is derived making assumptions that-

Correct Answer: (a) The flow is steady, non-viscous, incompressible and irrotational

29. The physical property, on which spectrophotometry is based, is-

Correct Answer: (a) Absorption and emission of radiation

30. The criterion for electronic spin resonance is-

Correct Answer: (c) Presence of unpaired electron in a molecule