SOLVED PAPER 2023 (CDS) (I) (General Studies)

Total Questions: 120

41. In plant cells, RNA is present in

Correct Answer: (d) nuclei, cytoplasm, mitochondria chloroplast and ribosomes
Solution:In plant cells, RNA is present in nuclei, nucleolus, cytoplasm, mitochondria chloroplast and ribosomes.

RNAs are of three different types-mRNA, RNA and tRNA.

mRNA and RNA are found in the cytoplasm and RNA in the nucleus. The ribosomes can be found free within the cytoplasm of a cell or attached to the endoplasmic reticulum called rough endoplasmic reticulum but do not present inside the nucleus.

42. In grasses intercalary meristem is usually located at

Correct Answer: (c) base of leaves
Solution:In grasses intercalary meristem is usually located at base of leaves. It helps in the elongation and growth of plants in nodes and internodes (stems and leaves) and also allows the stem and leaves (grasses) to grow longitudinally. The intercalary meristems are present in monocots at the base of the primordium leaf.

43. Xylem is a type of complex tissue in plants for upward conduction of water. Which one of the following xylem tissues consists of living cells?

Correct Answer: (c) Xylem parenchyma
Solution:Xylem parenchyma tissues consists of living cells. Xylem can be defined as a complex tissue that is composed of four types of cells - tracheids, trachea, xylem fibre and xylem parenchyma. The only living tissue in is xylem parenchyma.

44. Three resistors of resistances 112, 22 Ω and 33 Ω are connected in parallel. Their equivalent resistance is equal to

Correct Answer: (d) 6 Ω
Solution:Given, Three resistors of resistances are R₁ = 11 Ω, R2 = 22 Ω and R3 = 33 Ω are connected in parallel we know that the reciprocal of equivalent resistance of a number of resistor connected in parallel is equal to the sum of the reciprocals of the individual resistances. Then

45. The r.m.s. potential difference between the red live wire and black neutral wire in Indian domestic electric supply is

Correct Answer: (b) 220 V
Solution:The r.m.s (root mean square) potential difference between the red live wire and black neutral wire in Indian domestic supply is 220 volt. It is the difference between two points in a circuit in the amount of energy that the charge carriers have.

46. The hydrogen bomb and the uranium bomb are based, respectively on

Correct Answer: (a) nuclear fusion and fission.
Solution:The hydrogen bomb and the uranium bomb are based respectively on nuclear fusion and fission.

Here Nuclear fusion is the nuclear reaction in which two or more atomic nuclei are combined to from one or more different atomic nuclei and subatomic particles and nuclear fission is opposite of the nuclear fusion reaction where a heavy nucleous splits into two nuclei of nearly equal mass.

47. Sound and light waves are

Correct Answer: (a) respectively longitudinal and transverse in air.
Solution:Sound and light waves are respectively longitudinal and transverse in air. Because sound waves travel through compression and rarefactions in the medium. On the other hand light waves particles oscillate perpendicular to the direction in which the wave travel. And those wave do not require medium to travel.

48. A car moving with a speed of 12 m/s is subjected to brakes which produces a deceleration of 6m / (s ^ 2) The car takes 2 s to stop after the application of brakes. What is the distance covered by the car after the application of brakes?

Correct Answer: (a) 12 m
Solution:Given,
Initial velocity (u) = 12 m/s
Deacceleration (a) = - 6 m/s²
Here final velocity (v) = 0 m/s
The car takes time to stop. (+) = 2sec.
Applying Third equation of motion
v² = u² + 2as
0 = (12)² + 2(- 6) × s
0 = 144 - 12s
12s = 144, s = here distance
s = 12 meter

49. What is the chemical composition of a soda-acid type fire extinguisher?

Correct Answer: (a) Solution of sodium hydrogen carbonate and sulfuric acid.
Solution:Solution of sodium hydrogen carbonate and sulfuric acid is the chemical composition of a soda-acid type fire extinguisher. The chemicals used in Soda acid fire extinguisher are Sodium bicarbonate and Sulphuric acid. When they are used the gas evolved is carbon dioxide, which does not support combustion.

50. Consider the following statements.

While diluting concentrated nitric acid solution
1. the concentration of [H₃O⁺] ions/volume increases.
2. water must be added slowly to concentrated acid.
3. acid must be added slowly to water.

Which of the statements given above is/are correct?

Correct Answer: (c) Only 3
Solution:Only statement (3) is correct. The acid must always be added slowly to water with constant stirring. If water is added to a concentrated acid, the heat generated may cause the mixture to splash out and cause burns.