PYQ Vault

Day 153: CBSE Class 10 Science

5 questions (8 parts). Try each one first, then open its answer.

  1. Question 1

    The Human Eye and the Colourful World. Asked once: 2025 (same type asked 4 times)

    12
    Select the correct statement from the following :

    Tap an option to check your answer.

  2. Question 2

    The Human Eye and the Colourful World. Asked once: 2025 (same type asked 4 times)

    13
    The curvature of eye lens of human eye

    Tap an option to check your answer.

  3. Question 3

    Carbon and its Compounds. Asked once: 2022 (same type asked 4 times)

    2
    Draw the electron dot structure of the following : (a) Cyclohexane (b) Butane

  4. Question 4

    Electricity. Asked once: 2024 (same type asked 4 times)

    14
    An electric iron of resistance 20 Ω20\,\Omega draws a current of 5 A. The heat developed in the iron in 30 seconds is :

    Tap an option to check your answer.

  5. Question 5 (case study, 4 parts)

    Electricity. Asked once: 2024 (same type asked 4 times)

    In a domestic circuit five LED bulbs are arranged as shown. The source voltage is 220 V and the power rating of each bulb is marked in the circuit diagram. Based on the following circuit diagram, answer the following questions :
    39 (a)
    State what happens when (i) key K1\mathrm{K_1} is closed. (ii) key K2\mathrm{K_2} is closed.
    39 (b)
    Find the current drawn by the bulb B when it glows.
    39 (c)
    Calculate (i) the resistance of bulb B, and (ii) total resistance of the combination of four bulbs B, C, D and E.
    39 (c) OR
    What would happen to the glow of all the bulbs in the circuit when keys K1\mathrm{K_1} and K2\mathrm{K_2} both are closed and the bulb C suddenly get fused ? Give reason to justify your answer.