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Question 1 General Science
Which of the following statements is correct?\n\nStatement 1: The magnetic field lines produced around a straight current-carrying conductor form concentric circles centred along the wire.\nStatement 2: The direction of these magnetic field lines can be determined using the right-hand thumb rule.
- A. Both statements 1 and 2 are correct.
- B. Both statements 1 and 2 are incorrect.
- C. Statement 1 is incorrect, but 2 is correct.
- D. Statement 1 is correct, but 2 is incorrect.
Correct answer: A. Both statements 1 and 2 are correct.
Correct answer (Option A):\nAccording to Oersted's experiment and electromagnetism principles, the magnetic field lines around a straight current-carrying conductor form concentric circles with the wire at the center. Furthermore, Maxwell's Right-Hand Thumb Rule states that if you point your right thumb in the direction of the current, your curled fingers show the direction of the magnetic field lines. Therefore, both statements are fully accurate.\n\nWhy others are wrong:\nOptions B, C, and D are incorrect because they falsely claim one or both of the valid statements to be incorrect.\n\nStudy tip:\nRemember that the strength of this magnetic field is directly proportional to the current and inversely proportional to the distance from the wire.
Question 2 General Science
Which of the following statements is true about gravitational force of the Earth?
- A. It acts away from the centre of Earth.
- B. It depends on the mass of the object.
- C. It is a non-central force.
- D. It is independent of distance from Earth's centre.
Correct answer: B. It depends on the mass of the object.
Correct answer (Option B):\nThe gravitational force ($F$) exerted by the Earth on an object of mass $m$ is given by Newton's law of gravitation: $F = (G \times M \times m) / r^2$, where $M$ is the Earth's mass and $r$ is the distance from the center. This formula clearly shows that the gravitational force is directly proportional to the mass of the object.\n\nWhy others are wrong:\nOption A is wrong because gravity acts towards the center of the Earth. Option C is wrong because gravity is a classic central force. Option D is wrong because gravity varies inversely with the square of the distance from the center.\n\nStudy tip:\nWhile gravitational force depends on the mass of the object, the acceleration due to gravity ($g = G \times M / r^2$) is independent of the object's mass.
Question 3 General Science
What is the sequence of stages involved in the budding process of hydra?
- A. Bud maturation → Bud initiation → New individual → Bud detachment
- B. Bud initiation → Bud maturation → Bud detachment → New individual
- C. Bud detachment → New individual → Bud maturation → Bud initiation
- D. Bud initiation → Bud detachment → Bud maturation → New individual
Correct answer: B. Bud initiation → Bud maturation → Bud detachment → New individual
Correct answer (Option B):\nBudding in Hydra is a form of asexual reproduction. The precise chronological process begins with an outgrowth or bud due to repeated cell division at one specific site (Bud initiation). This bud then develops tentacles and mouth parts while attached to the parent (Bud maturation). Once fully developed, the bud separates from the parent organism (Bud detachment) to live independently as a self-sufficient entity (New individual).\n\nWhy others are wrong:\nOptions A, C, and D list the steps out of chronological sequence, placing detachment before maturation or maturation before initiation, which is biologically impossible.\n\nStudy tip:\nBudding is also observed in unicellular organisms like Yeast, but in Hydra, it occurs in a multicellular body structure.
Question 4 General Science
பின்வரும் செயல்பாடுகளில் எது பொருளின் துகள்களுக்கு இடையில் இடைவெளிகள் இருப்பதை நிரூபிக்கிறது? (Which of the following activities demonstrates that there are spaces between particles of matter?)
- A. ஒரு திரவத்தை உறைய வைத்தல் (Freezing a liquid)
- B. ஒரு திடப்பொருளை சூடாக்குதல் (Heating a solid)
- C. சர்க்கரையை தண்ணீரில் கரைத்தல் (Dissolving sugar in water)
- D. ஒரு வாயுவை அழுத்துதல் (Compressing a gas)
Correct answer: C. சர்க்கரையை தண்ணீரில் கரைத்தல் (Dissolving sugar in water)
Correct answer (Option C):\nWhen sugar is dissolved in water, the sugar particles completely disappear into the water without increasing its volume significantly. This happens because the sugar particles occupy the intermolecular spaces available between the water molecules, directly proving that matter is made of particles with spaces between them.\n\nWhy others are wrong:\nOption A demonstrates a phase change due to kinetic energy loss. Option B shows thermal expansion. Option D highlights the high compressibility of gaseous matter due to large gaps, but dissolving is the definitive proof of microscopic interstitial spacing.\n\nRemember:\nThis concept is a core tenet of the kinetic molecular theory of matter.
Question 5 General Science
What is the defining characteristic of an unsaturated carbon compound?
- A. It contains at least one double or triple bond between carbon atoms.
- B. It forms only cyclic structures.
- C. All carbon atoms are linked by only single bonds.
- D. It always contains a functional group with oxygen.
Correct answer: A. It contains at least one double or triple bond between carbon atoms.
Correct answer (Option A):\nCarbon compounds are classified into saturated and unsaturated compounds. Saturated compounds contain only single covalent bonds between carbon atoms (alkanes). Unsaturated carbon compounds are defined by the presence of at least one double bond (alkenes) or triple bond (alkynes) between carbon atoms, making them more reactive.\n\nWhy others are wrong:\nOption B is incorrect because unsaturated compounds can be straight-chain, branched, or cyclic. Option C defines saturated hydrocarbons. Option D is false as many unsaturated hydrocarbons (like ethene or ethyne) contain only carbon and hydrogen.\n\nStudy tip:\nUnsaturated hydrocarbons undergo characteristic addition reactions (e.g., hydrogenation) to become saturated.
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