UGC NTA NET/JRF Exam, Forensic Science, August-2024

Total Questions: 100

81. Match the List-I with List-II.

List-I (Polymers)	List-II (Structures)
A. Polypropene	I. Phenol-formaldehyde network structure
B. Polystyrene	II. Structure with chlorine atom (- $(-\text{Cl})$
C. Polyvinyl Chloride	III. Structure with phenyl group C₆H₅
D. Bakelite	IV. Structure with methyl group (-CH₃)

1. A-III, B-IV, C-II, D-I
2. A-IV, B-III, C-II, D-I
3. A-IV, B-III, C-I, D-II
4. A-I, B-II, C-IV, D-III

Correct Answer: 2. A-IV, B-III, C-II, D-I

Solution:

Matching the polymers with their correct structures:

• A-IV: Polypropene → Structure IV
Polypropene (also known as polypropylene) is a polymer formed from the monomer propene (CH₂=CH-CH₃). The structure shows a repeating unit with a -CH₃ (methyl group) attached to the carbon chain, matching structure IV.

• B-III: Polystyrene → Structure III
Polystyrene is made from the monomer styrene (C₆H₅-CH=CH₂). The polymer structure has a phenyl group (C₆H₅) attached to every other carbon in the chain. This corresponds to structure III.

• C-II: Polyvinyl Chloride → Structure II
PVC is derived from vinyl chloride (CH₂=CHCI). The repeating unit shows a -Cl (chlorine) atom attached to the carbon backbone. This matches structure II.

• D-I: Bakelite → Structure I
Bakelite is a thermosetting polymer formed from phenol and formaldehyde. The structure in option I shows a phenol-formaldehyde resin, which is typical of Bakelite. This polymer has aromatic rings with hydroxyl groups connected via methylene bridges. Thus, the correct matching is: A-IV, B-III, С-II, D-I.

82. Match the List-I with List-II.

List-I	List-II
A. The efficiency of the shape of the projectile to overcome the air resistance, is called	I. Ignition-time
B. The index of the ability of the projectile to overcome air-resistance is called	II. Form-factor
C. The projectile changing their direction after striking the surface at the low angles is called	III. Ballistic-Coefficient
D. The interval from the impact on the primer of the cartridge until the pressure rises enough to start the bullet from its seat is	IV. Ricochet

Choose the correct answer from the options given below:

1. A-II, B-III, C-IV, D-I
2. A-I, B-IV, C-II, D-III
3. A-IV, B-I, C-III, D-II
4. A-III, B-II, C-IV, D-I

Correct Answer: 1. A-II, B-III, C-IV, D-I

Solution:

A-II: The efficiency of the shape of the projectile to overcome air resistance is called Form-factor. The form factor compares the drag characteristics of a given bullet shape with that of a standard projectile. It determines how aerodynamic the shape is.

B-III: The index of the ability of the projectile to overcome air-resistance is called Ballistic Coefficient. The ballistic coefficient (BC) is a measure of a projectile's ability to overcome air resistance in flight. Higher BC means flatter trajectory and better energy retention.

C-IV: The projectile changing direction after striking the surface at low angles is called Ricochet. A ricochet occurs when a projectile bounces or glances off a surface instead of embedding or penetrating.

D-I: The interval from the impact on the primer until bullet movement is called Ignition-time. Ignition time is the delay between primer strike and the bullet starting to move, representing the time for powder ignition and pressure buildup.

83. Match the List-I with List-II.

List-I (Name)	List-II (Alkaloid)
A. Coniine	I. Solanaceous
B. Atropine	II. Coca
C. Hygrine	III. Hemlock
D. Colchicine	IV. Meadow saffron

Choose the correct answer from the options given below:

1. A-I, B-III, C-II, D-IV
2. A-III, B-I, C-II, D-IV
3. A-III, B-I, C-IV, D-II
4. A-I, B-II, C-III, D-I

Correct Answer: 2. A-III, B-I, C-II, D-IV

Solution:

A-III: Coniine - Hemlock
Coniine is a neurotoxic alkaloid found in the hemlock plant, historically known for its toxic effects.

B-I: Atropine - Solanaceous
Atropine is a tropane alkaloid obtained from plants of the Solanaceae family, such as Atropa belladonna.

C-II: Hygrine - Cocа
Hygrine is an alkaloid found in the leaves of the coca plant, often associated with cocaine.

D-IV: Colchicine - Meadow saffron
Colchicine is derived from the plant Colchicum autumnale, commonly known as meadow saffron, and used in the treatment of gout.

84. Match the List-I with List-II.

List-I	List-II
A. An electric current produced by oxidation/reduction processes in an electrochemical cell	I. Polarography
B. An electrochemical cell that provides energy during its operation	II. Amperostat
C. An instrument that maintains a constant current in an electrochemical cell	III. Galvanic cell
D. Voltammetry with a dropping mercury electrode	IV. Faradaic current

Choose the correct answer from the options given below:

1. A-IV, B-III, C-II, D-I
2. A-I, B-II, C-III, D-IV
3. A-III, B-IV, C-II, D-I
4. A-IV, B-III, C-I, D-II

Correct Answer: 1. A-IV, B-III, C-II, D-I

Solution:

• A-IV: Electric current produced by redox reactions → Faradaic current A Faradaic current is generated by oxidation-reduction reactions occurring at electrodes in an electrochemical cell.

• B-III: Electrochemical cell that provides energy →Galvanic cell A galvanic cell (or voltaic cell) converts chemical energy into electrical energy during spontaneous redox reactions.

• C-II: Instrument maintaining constant current→ Amperostat An amperostat controls and maintains a constant current in an electrochemical cell.

• D-I: Voltammetry with a dropping mercury electrode → Polarography Polarography is a type of voltammetry using a dropping mercury electrode to study redox behaviour of analytes.

85. Match the List-I with List-II.

List-I	List-II
A. Rotation in small circles forming a rosette pattern	I. Precession
B. Wobbling or circular yawing in a spiral fashion around the center of mass	II. Tumbling
C. Forward rotation around the center of mass of the bullet	III. Yaw
D. Deviation of a bullet in its longitudinal axis from a straight line of flight	IV. Nutation

Choose the correct answer from the options given below:

1. A-I, B-II, C-III, D IV
2. A-III, B-IV, C-I, D-II
3. A-II, B-III, C-IV, D-I
4. A-IV, B-I, C-II, D-III

Correct Answer: 4. A-IV, B-I, C-II, D-III

Solution:

A-IV: Rotation in small circles forming a rosette pattern → Nutation Nutation is a secondary motion where the bullet axis traces a small rosette pattern around the precession path.

B-I: Wobbling or spiral yawing around center of mass → Precession Precession is the gradual rotation of the axis of a spinning bullet around its center of mass.

C-II: Forward rotation around center of mass→ Tumbling Tumbling is a loss of stability, where the bullet rotates end-over-end instead of following a stable spin.

D-III: Deviation from a straight path→ Yaw Yaw is the angular deviation of a bullet's longitudinal axis from its line of flight, affecting accuracy and drag.

86. Match the List-I with List-II.

List-I (Skull suture)	List-II (Feature)
A. Squamosal	I. unites frontal bone with parietal bone
B. Coronal suture	II. unites the squamous portion of the temporal bone with the parietal bone
C. Sagittal suture	III. unites the parietal bones with occipital bone
D. Lambdoid suture	IV. unites the 2 parietal bones in the middle

Choose the correct answer from the options given below:

1. A-II, B-III, C-I, D-IV
2. A-II, B-I, C-IV, D-III
3. A-I, B-III, C-IV, D-II
4. A-II, B-IV, C-I, D-III

Correct Answer: 2. A-II, B-I, C-IV, D-III

Solution:

A-II: Squamosal suture - unites the squamous portion of the temporal bone with the parietal bone The squamosal suture is the joint between the parietal bone and the squamous part of the temporal bone on the lateral side of the skull.

B-I: Coronal suture - unites frontal bone with parietal bone The coronal suture runs horizontally across the top of the skull, uniting the frontal bone with the two parietal bones.

C-IV: Sagittal suture - unites the two parietal bones in the middle The sagittal suture runs antero-posteriorly, dividing the skull into right and left halves and joining the two parietal bones.

D-III: Lambdoid suture - unites the parietal bones with the occipital bone The lambdoid suture is found on the posterior side of the skull and connects the parietal bones to the occipital bone.

87. Match the List-I with List-II.

List-I (Component)	List-II (Purpose)
A. CPU	I. Controls the flow of data to and from the primary storage
B. RAM	II. Interprets and carries out the basic instructions that operate a computer
C. ROM	III. Temporary storage for data and instructions
D. Control Unit	IV. Contains fixed, startup instructions

Choose the correct answer from the options given below:

1. A-I, B-II, C-III, D-IV
2. A-III, B-IV, C-II, D-I
3. A-IV, B-I, C-II, D-III
4. A-II, B-III, C-IV, D-I

Correct Answer: 3. A-IV, B-I, C-II, D-III

Solution:

A-IV: Amino resins - Crosslinking agent for baking enamels in kitchen appliances Amino resins like melamine formaldehyde are used as crosslinking agents in baking enamels, especially in white goods and kitchen appliances.

B-I: Nitrocellulose resins - Lacquer coating for tools Nitrocellulose is used in lacquers and fast-drying coatings, commonly found on tools and wooden items.

С-II: Ероxy resins - Automotive thermosetting primer and corrosion protection Epoxy resins are known for their excellent adhesion and chemical resistance, widely used in automobile primers and anticorrosion paints.

D-III: Polyurethane resins - Aircraft and automobile coating Polyurethane coatings are flexible and durable, widely used in high-performance coatings for automotive and aerospace industries.

88. Match the List-I with List-II.

List-I (Search Engines)	List-II (Description)
A. Google	I. One of the most popular search engines in Russia.
B. Bing	II. The most popular search engine in the world.
C. Baidu	III. Microsoft’s search engine.
D. Yandex	IV. The most popular search engine in China.

Choose the correct answer from the options given below:

1. A-I, B-II, C-III, DIV
2. A-IV, B-I, C-II, D-III
3. A-II, B-I, C-IV, D-III
4. A-III, B-IV, C-I, D-II

Correct Answer: 3. A-II, B-I, C-IV, D-III

Solution:

A-II: Amiton - A nerve agent Amiton is an organophosphate nerve agent, originally developed as a pesticide.

B-I: ANFO - A mixture of ammonium nitrate and fuel oil ANFO (Ammonium Nitrate Fuel Oil) is a widely used bulk industrial explosive.

C-IV: Chloroacetophenone - Normally used as tear gas Chloroacetophenone (CN) is used as a lachrymatory agent (tear gas) in riot control.

D-III: Black powder - A mixture of potassium nitrate, sulphur, and charcoal Black powder is the oldest known explosive propellant, made from KNO₃, S, and C.

89. Match the List-I with List-II.

List-I (Metallic Poison)	List-II (Atomic Number)
A. Mercury	I. 84
B. Polonium	II. 82
C. Arsenic	III. 80
D. Lead	IV. 33

Choose the correct answer from the options given below:

1. A-II, B-III, C-IV, D-I
2. A-III, B-I, C-IV, D-II
3. A-I, B-II, C-III, D-IV
4. A-IV, B-II, C-I, D-III

Correct Answer: 2. A-III, B-I, C-IV, D-II

Solution:

A-III: Mercury - Atomic number 80 Mercury (Hg) is a toxic heavy metal with atomic number 80.

B-I: Polonium - Atomic number 84 Polonium (Po) is a rare radioactive element, atomic number 84.

C-IV: Arsenic - Atomic number 33 Arsenic (As) is a well-known poison, atomic number 33.
D-II: Lead - Atomic number 82 Lead (Pb) is another toxic metal, with atomic number 82.