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Logic followed here is based on the common word comparison method.

Given:

‘conflict of interest’ is coded as ‘gu ky bz’

‘end this conflict’ is coded as ‘ky tg cn’

The code for conflict is ky.

Hence, the correct answer is "Option 1".

Given:

Let us first decode the given symbols and then draw a family tree.

On checking: Z × C ge L o M @ N

1. Z × C - 'Z × C' means 'Z is the daughter of C'.

2. C ge L - 'C ge L' means 'C is the wife of L'.

3. L o M - 'L o M' means 'L is the father of M'.

4. M @ N - 'M @ N' means 'M is the brother of N'.

Therefore, Z and M are siblings of N, and all are children of L and C. Since Z is female, she is the sister of N.

Hence, the correct answer is 'Option 3'.

Sign Interchanges

Equation Transformation

The original equation is: 6 ÷ 2 + 24 × 6 − 4 →

By substituting the signs according to the given logic:

New Equation: 

= 6 × 2 − 24 ÷ 6 + 4

= 6 × 2 - 4 + 4

= 12 - 4 + 4

= 12

Therefore, the value that will come in the place of ? is 12.

Hence, the correct answer is "Option 4".

Given Series:

(Left) D U A L J X E I H R S B W P K T C V M F Y (Right)

Required pattern:

Consonant → Vowel → Vowel

Checking the series:

(Left) D U A L J X E I H R S B W P K T C V M F Y (Right)

Vowels satisfying the condition:

→ U in (D U A)

→ E in (X E I)

Therefore, there are 2 such vowels.

Hence, the correct answer is "Option 3".

Given:

1. Ankur starts from Point A and drives 11 km towards east. 2. He then takes a right turn, drives 7 km. 3. Then he turns right and drives 14 km. 4. He then takes a right turn and drives 12 km. 5. He takes a final right turn, drives 3 km and stops at Point P.

Following the movements described in the question, we can track Ankur path step-by-step from Point A to Point P.

Therefore, he should drive 5 km to the south to reach Point A.

Hence, the correct answer is "Option 3".

The correct answer is Graphite.

Key Points

• Graphite is a unique allotrope of carbon that functions as a conductor despite the general insulating nature of non-metals.
• The crystal structure of graphite consists of hexagonal layers where each carbon atom is sp² hybridized and covalently bonded to three other carbon atoms.
• Because carbon has four valence electrons, only three are utilized in forming strong sigma bonds within the planar sheets.
• The fourth valence electron is located in an unhybridized p-orbital perpendicular to the plane of the carbon atoms.
• These p-orbitals overlap laterally to form a delocalized pi-electron system that extends across the entire layer of the lattice.
• The presence of these mobile, delocalized electrons allows graphite to conduct electricity efficiently along the direction of its layers when a potential difference is applied.
• In contrast, the van der Waals forces between the layers are weak, contributing to graphite's lubricating properties but not its conductivity.

 Additional Information

• Sulphur:
• Exists predominantly as S₈ molecules with a puckered ring structure.
• It is an insulator because all its valence electrons are locked in covalent bonds, leaving no free electrons for conduction.
• Phosphorus:
• Found in various allotropes like white phosphorus (P₄) and red phosphorus (polymeric).
• These structures consist of discrete molecules or chains where electrons are localized, making it a poor conductor.
• Iodine:
• A halogen that forms diatomic molecules (I₂) arranged in a molecular crystal lattice.
• The lack of delocalized electrons or ions in the solid state prevents the flow of electric current.
• Diamond:
• Another carbon allotrope with sp³ hybridization forming a three-dimensional tetrahedral structure.
• All valence electrons are involved in strong C-C bonds, resulting in it being an excellent electrical insulator.

The correct answer is Both (i) and (iii).

Key Points

• In a distance-time graph, the slope (gradient) is defined as the change in distance divided by the change in time (Δd/Δt), which represents the speed of the object. Acceleration is the rate of change of velocity over time and is not directly represented by the slope of a distance-time graph. Hence, statement (i) is incorrect.
• For a body in uniform motion, the graph is a straight line. A lesser slope (a flatter line) indicates that the body covers less distance in a given time interval, meaning the magnitude of its speed is lower. Hence, statement (ii) is correct.
• The area under a graph is the integral of the y-axis variable with respect to the x-axis variable. For a distance-time graph, this would be the product of distance and time (unit: meter·seconds), which does not correspond to speed (unit: meters per second) or any standard kinematic quantity. Hence, statement (iii) is incorrect.

 Additional Information

• Uniform Motion Characteristics:
• An object is in uniform motion if it travels in a straight line and covers equal distances in equal intervals of time.
• In this state, the velocity is constant, and the resultant acceleration is zero.
• The distance-time graph is always a linear plot with a constant gradient.
• Speed-Time (or Velocity-Time) Graphs:
• In a velocity-time graph, the slope represent the acceleration of the body.
• The area under the velocity-time graph represents the displacement or total distance traveled by the body.
• For uniform motion, the velocity-time graph is a horizontal line parallel to the time axis, indicating a slope of zero (zero acceleration).

The correct answer is − 2000 N.

Key Points

• According to Newton's Second Law of Motion, the force (F) applied to an object is directly proportional to the rate of change of its linear momentum, commonly expressed as F = m × a, where 'm' is mass and 'a' is acceleration.
• The acceleration (a) of the car is calculated using the first equation of motion or the definition of acceleration: a = (v − u) / t. Here, u is the initial velocity, v is the final velocity, and t is the time interval.
• Given parameters: Mass (m) = 1000 kg, Initial Velocity (u) = 20 m/s, Final Velocity (v) = 0 m/s (as the car comes to rest), and Time (t) = 10 s.
• Calculating acceleration: a = (0 − 20) / 10 = −2 m/s². The negative sign indicates retardation or deceleration due to braking.
• Applying the force formula: F = 1000 kg × (−2 m/s²) = −2000 N. The negative sign signifies that the braking force is acting in the direction opposite to the car's motion.

 Additional Information

• Kinematics and Dynamics:
• Newton (N): The SI unit of force. One Newton is the force required to accelerate a mass of 1 kg at a rate of 1 m/s².
• Retardation: It is defined as negative acceleration. In this case, the brakes provide a resistive force that reduces the kinetic energy of the vehicle.
• Impulse: The change in momentum (m × Δv) is also known as impulse, which is equal to the product of force and the time interval (F × t).
• Direction of Force: In physics, the sign of the force indicates vector direction relative to the chosen coordinate system; a negative result confirms it is a resistive force.

The correct answer is Power.

Key Points

• The Power of a lens represents its capacity to bend light rays. It is defined as the tangent of the angle by which it converges or diverges a beam of light falling at a unit distant from the optical center.
• It is mathematically defined as the reciprocal of the focal length (f) of the lens. The formula is expressed as P = 1/f, where the focal length must be in meters.
• The SI unit of optical power is the Dioptre (represented by D). One Dioptre is equal to 1 m⁻¹.
• A convex lens has a positive focal length, and therefore its power is positive. Conversely, a concave lens has a negative focal length, making its power negative.
• A lens with a shorter focal length has a greater ability to bend light rays, meaning it has higher power compared to a lens with a longer focal length.

 Additional Information

• Magnification:
• It is the ratio of the height of the image to the height of the object.
• It indicates how many times the image is enlarged or diminished relative to the object size.
• Aperture:
• It refers to the effective diameter of the light-transmitting area of the lens.
• The intensity of the image formed depends on the size of the aperture, as it controls the amount of light entering the system.
• Image Distance:
• It is the distance between the optical center of the lens and the position of the image formed, denoted by v.
• According to the Lens Formula, 1/f = 1/v − 1/u, where u is the object distance.

The correct answer is They contain their own DNA and ribosomes.

Key Points

• Mitochondria are often referred to as the powerhouse of the cell because they are the primary sites for ATP (Adenosine Triphosphate) synthesis through aerobic respiration.
• They are classified as semi-autonomous organelles because they possess their own genetic material, known as mitochondrial DNA (mtDNA), and their own ribosomes.
• The mtDNA is typically a small, circular molecule that encodes for several essential proteins, tRNAs, and rRNAs required for the organelle's function.
• Mitochondria contain 70S ribosomes, which are structurally similar to those found in prokaryotic organisms, allowing them to perform protein synthesis within the mitochondrial matrix independently of the cell nucleus.
• While most cellular proteins are encoded by nuclear DNA and imported from the cytoplasm, these organelles produce about 13 critical polypeptides involved in the oxidative phosphorylation system.

 Additional Information

• Endosymbiotic Theory:
• The presence of independent DNA and ribosomes supports the theory that mitochondria evolved from an ancient endosymbiosis between a primitive eukaryote and an aerobic bacterium.
• Structural Components:
• Double Membrane: Mitochondria consist of an inner membrane and an outer membrane. The inner membrane is folded into cristae to maximize the surface area for energy production.
• Porous Outer Membrane: This membrane contains special proteins called porins, which permit the free diffusion of molecules smaller than 5,000 Daltons.
• ATP Production:
• While mitochondria produce ATP, this is a metabolic function and does not directly provide the genetic blueprint or machinery for protein manufacturing.