PYQ Vault

Day 220: CBSE Class 10 Science

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

  1. Question 1

    Our Environment. Asked once: 2023 (same type asked 4 times)

    26
    Use of several pesticides which results in excessive accumulation of pesticides in rivers or ponds, is a matter of deep concern. Justify this statement.

  2. Question 2

    Our Environment. Asked once: 2023 (same type asked 4 times)

    21
    (i) State the essential function performed by ozone at the higher levels of the atmosphere. (ii) Why was there a sharp drop in the amount of ozone in the atmosphere in 1980’s.

  3. Question 3

    The Human Eye and the Colourful World. Asked once: 2023 (same type asked 4 times)

    12
    The change in the focal length of an eye lens in human beings is caused by the action of

    Tap an option to check your answer.

  4. Question 4

    Electricity. Asked once: 2023 (same type asked 3 times)

    34
    There are three resistors of 10 Ω10\,\Omega, 20 Ω20\,\Omega and 30 Ω30\,\Omega joined in parallel in a circuit. The potential difference across the electric circuit is 10 V. (a) Draw a circuit diagram for the above case. (b) Find the total resistance of the combination of resistors. (c) Calculate the electric current drawn from the same source.

  5. Question 5

    Light — Reflection and Refraction. Asked once: 2023 (same type asked 3 times)

    29
    A student wants to project the image of a candle flame on a screen 60 cm in front of a mirror by keeping the candle at a distance of 15 cm from its pole. (a) Name the type of mirror used. (b) Also calculate : (i) Magnification of the image produced (ii) Distance between object and its image (c) Draw a ray diagram to show the image formation.