PYQ Vault

Day 22: CBSE Class 10 Science

5 questions. Try each one first, then open its answer.

  1. Question 1

    Life Processes. Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)

    11
    Why the lungs always contain a residual volume of air ?

  2. Question 2

    Light — Reflection and Refraction. Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)

    36
    An object is placed at a distance of 30 cm in front of a convex lens of focal length 15 cm. Use lens formula to determine the position of the image. What will be the size of the image in this case ?

  3. Question 3

    Light — Reflection and Refraction. Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)

    37
    A mirror used for rear-view of an automobile has a focal length 2.0 m. If a car is located at 8.0 m from the mirror - (a) Find out the position of the image of this car as seen in the mirror. (b) Draw the ray-diagram for image formation by the rear-view mirror.

  4. Question 4

    Light — Reflection and Refraction. Asked 2 times: 2023*, 2026 (* = numbers or wording changed that year)

    33
    A ray of light enters into medium B from medium A as shown in the given figure : (a) Which one of these two media is optically denser than the other medium ? Justify your answer. (b) If the speed of light in medium A is VA\mathrm{V_A} and in medium B is VB\mathrm{V_B}, then what is the refractive index of medium B with respect to medium A ?

  5. Question 5

    Light — Reflection and Refraction. Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)

    35
    (a) Observe the given ray diagram and compare : (i) the speed of light in medium A and the speed of light in medium B. (ii) the optical densities of medium B and medium C. (b) Draw a ray diagram for refraction where the optical density of medium ‘A’ becomes equal to the optical density of medium ‘C’ and optical density of medium ‘B’ is greater than the optical density of medium ‘A’ and medium ‘C’.