SolveItClass 10 · NCERT

NCERT Solutions · Class 10 Science Light - Reflection and Refraction

17 questions · 17 still being checked

EXERCISES 1–10 (part 1 of 2)

  1. Exercise 1

    Which one of the following materials cannot be used to make a lens?
    (a)
    Water
    (b)
    Glass
    (c)
    Plastic
    (d)
    Clay
    NCERT’s answer
    (d)

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  2. Exercise 2

    The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object?
    (a)
    Between the principal focus and the centre of curvature
    (b)
    At the centre of curvature
    (c)
    Beyond the centre of curvature
    (d)
    Between the pole of the mirror and its principal focus.
    NCERT’s answer
    (d)

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  3. Exercise 3

    Where should an object be placed in front of a convex lens to get a real image of the size of the object?
    (a)
    At the principal focus of the lens
    (b)
    At twice the focal length
    (c)
    At infinity
    (d)
    Between the optical centre of the lens and its principal focus.
    NCERT’s answer
    (b)

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  4. Exercise 4

    A spherical mirror and a thin spherical lens have each a focal length of –15\displaystyle 15 cm. The mirror and the lens are likely to be
    (a)
    both concave.
    (b)
    both convex. Light – Reflection and Refraction
    (c)
    the mirror is concave and the lens is convex.
    (d)
    the mirror is convex, but the lens is concave.
    NCERT’s answer
    (a)

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  5. Exercise 5

    No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be
    (a)
    only plane.
    (b)
    only concave.
    (c)
    only convex.
    (d)
    either plane or convex.
    NCERT’s answer
    (d)

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  6. Exercise 6

    Which of the following lenses would you prefer to use while reading small letters found in a dictionary?
    (a)
    A convex lens of focal length 50\displaystyle 50 cm.
    (b)
    A concave lens of focal length 50\displaystyle 50 cm.
    (c)
    A convex lens of focal length 5\displaystyle 5 cm.
    (d)
    A concave lens of focal length 5\displaystyle 5 cm.
    NCERT’s answer
    (c)

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  7. Exercise 7

    We wish to obtain an erect image of an object, using a concave mirror of focal length 15\displaystyle 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.
    NCERT’s answer
    Distance less than $\displaystyle 15$ cm; virtual; Enlarged.

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  8. Exercise 8

    Name the type of mirror used in the following situations.
    (a)
    Headlights of a car.
    (b)
    Side/rear-view mirror of a vehicle.
    (c)
    Solar furnace. Support your answer with reason.

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  9. Exercise 9

    One-half of a convex lens is covered with a black paper. Will this lens produce a complete image of the object? Verify your answer experimentally. Explain your observations.
    NCERT’s answer
    Yes

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  10. Exercise 10

    An object 5\displaystyle 5 cm in length is held 25\displaystyle 25 cm away from a converging lens of focal length 10\displaystyle 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.
    NCERT’s answer
    16.$\displaystyle 7$ cm from the lens on the other side; $\displaystyle 3.3$ cm, reduced; real, inverted.

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