1. (i) From the ray diagram, the image formed is real, inverted, and diminished because the object is placed beyond 2F₁ of a convex lens. (ii) The magnification will be –1 when the object is placed at 2F₁, as then the image is formed at 2F₂, real, inverted, and of the same size as the object.

    (i) From the ray diagram, the image formed is real, inverted, and diminished because the object is placed beyond 2F₁ of a convex lens.

    (ii) The magnification will be –1 when the object is placed at 2F₁, as then the image is formed at 2F₂, real, inverted, and of the same size as the object.

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  2. ANSWER: [A] Explanation: Assertion (A) states that magnetic field lines never intersect, which is true. Reason (R) correctly explains this, as intersection would mean two directions of the magnetic field at one point, which is impossible. Hence, both A and R are true, and R is the correct explanatioRead more

    ANSWER: [A]

    Explanation: Assertion (A) states that magnetic field lines never intersect, which is true. Reason (R) correctly explains this, as intersection would mean two directions of the magnetic field at one point, which is impossible. Hence, both A and R are true, and R is the correct explanation of A.

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  3. The diagram shows myopia (nearsightedness), where the image forms in front of the retina. This defect occurs when the focal length of the eye lens is too short (III) or the eyeball becomes too long (IV). Hence, the correct option is (d) III and IV.

    The diagram shows myopia (nearsightedness), where the image forms in front of the retina. This defect occurs when the focal length of the eye lens is too short (III) or the eyeball becomes too long (IV). Hence, the correct option is (d) III and IV.

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  4. When a narrow parallel beam of light passes through an optical device and emerges displaced laterally but parallel to itself, the device must be a glass slab. A plane mirror reflects without displacement, a convex lens converges or diverges light, and a prism deviates light angularly. Hence, the corRead more

    When a narrow parallel beam of light passes through an optical device and emerges displaced laterally but parallel to itself, the device must be a glass slab. A plane mirror reflects without displacement, a convex lens converges or diverges light, and a prism deviates light angularly. Hence, the correct answer is (c) glass slab, which produces lateral displacement without altering the beam’s direction of propagation.

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  5. (a) The bond formed between X and Y is a covalent bond, because element X (carbon) shares its valence electrons with element Y (hydrogen - like or sodium) to achieve a stable configuration. (b) Four valence electrons from X and one valence electron from Y participate in bond formation, as X needs toRead more

    (a) The bond formed between X and Y is a covalent bond, because element X (carbon) shares its valence electrons with element Y (hydrogen – like or sodium) to achieve a stable configuration.

    (b) Four valence electrons from X and one valence electron from Y participate in bond formation, as X needs to share electrons to complete its octet.
    (c) The chemical formula of the compound is , as X forms four single bonds with four Y atoms.

    (d) The compound is generally a poor conductor of electricity because covalent compounds do not have free ions or electrons to conduct current.

    (e) When element Y (like Na) reacts with ethanoic acid , hydrogen gas is evolved, and the salt sodium ethanoate is formed.

    CH3COOH + Na → CH3COONa + H2 ↑

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