UPSC CAPF AC (Assistant Commandants) Exam 07 Aug 2022 Paper 1 (General Studies and Intelligence) (Answer Key)

21. Which one of the following is not the unit of pressure?
(a) pascal (Pa)
(b) N/m²
(c) J/m²
(d) bar

22. Which one of the following materials cannot be used to make a convex lens?
(a) Aluminium
(b) Glass
(c) Sapphire
(d) Water

23. The optical phenomenon responsible for the blue colour of sky is
(a) dispersion
(b) reflection
(c) refraction
(d) scattering

24. The electrical device used for converting mechanical energy into electrical energy is called
(a) voltmeter
(b) ammeter
(c) motor
(d) generator

25. The magnitude of focal length of a concave lens is 2 m. What is the power of the lens?
(a) +0.5 dioptre
(b) -0.5 dioptre
(c) +2.0 dioptre
(d) -1.0 dioptre

26. At the time of short circuit, the current in an electric circuit
(a) becomes zero
(b) remains same
(c) increases sharply
(d) decreases sharply

27. If the linear momentum of a moving object changes by two times, then its kinetic energy will change by a factor of
(a) 2
(b) 4
(c) 6
(d) 8

28. Which one of the following oxides reacts with both acid and base?
(a) Aluminium oxide
(b) Calcium oxide
(c) Sodium ium oxide
(d) Potassium oxide

29. Which of the following makes bread soft and spongy when baking soda is t added?
(a) Sodium salt of acid
(b) NaHCO₃
(c) CO₂
(d) H₂O

30. The average age of father and elder son is 35 years, the average age of father and younger son is 32 years and the average age of the two sons is 17 years. What is the average age of the father and his two sons?
(a) 30 years
(b) 27 years
(c) 28 years
(d) 29 years

31. A number is 124 more than its one-third. What is that number?
(a) 194
(b) 180
(c) 189
(d) 186

32. A car travels 3/4th of the distance at a speed of 60 km/hr and the remaining 1/4th of the distance at a speed of V km/hr. If the average speed for the full journey is 50 km/hr then the value of v is
(a) 40
(b) 30
(c) 100/3
(d) 35

33. Suppose A and B can complete a work together in 10 days. If B alone can complete the work in 15 days, then in how many days can A alone finish the work?
(a) 20 days
(b) 24 days
(c) 25 days
(d) 30 days

34. If the average of the first four of five numbers in decreasing order is 25 and the average of the last four numbers is 20, then what is the difference between the first and the last number?
(a) 5
(b) 10
(c) 15
(d) 20

35. Borax is prepared from
(a) calcium carbonate
(b) magnesium carbonate
(c) potassium carbonate
(d) sodium carbonate

36. Cinnabar is an ore of
(a) mercury
(b) zinc
(c) copper
(d) lead

37. White gold is an alloy of
(a) gold, nickel and palladium
(b) gold, cobalt and palladium
(c) gold, titanium and platinum
(d) gold, magnesium and palladium

38. Hydrogenation of alkenes can be carried out in the presence of
(a) copper
(b) zinc
(c) aluminium
(d) nickel

39. Calcium oxide reacts with water to produce slaked lime. It is an example of
(a) combination reaction
(b) decomposition reaction
(c) oxidation reaction
(d) addition reaction

40. The atomic radius of hydrogen atom is
(a) 37 nanometer
(b) 37 picometer
(c) 17 picometer
(d) 57 picometer