PYQ Vault

Day 36: CBSE Class 10 Science

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

  1. Question 1

    Our Environment. Asked 2 times: 2022*, 2023 (* = numbers or wording changed that year)

    25
    “Although gardens are created by man but they are considered to be an ecosystem.” Justify this statement.

  2. Question 2

    Carbon and its Compounds. This type asked 5 times: 2022, 2023, 2024, 2025, 2026. This one: 2026

    29 (A)
    (i) Carbon cannot form C4+\mathrm{C^{4+}} cation and C4−\mathrm{C^{4-}} anion. Explain. (ii) Define homologous series of carbon compounds. Why are the melting and boiling points of C4H10\mathrm{C_4H_{10}} higher than C3H8\mathrm{C_3H_8} or C2H6\mathrm{C_2H_6} ? (iii) What happens when ethanol is heated with acidified potassium dichromate ?

  3. Question 3

    Electricity. This type asked 5 times: 2022, 2023, 2024, 2025, 2026. This one: 2026

    34 (b)
    An electric heater is rated 220 V; 11 A. Calculate the power consumed if the heater is operated at 200 V.

  4. Question 4

    Magnetic Effects of Electric Current. This type asked 5 times: 2022, 2023, 2024, 2025, 2026. This one: 2026

    39 (B)
    (i) Draw a diagram, showing the magnetic field lines in and around the current carrying solenoid. Write any two salient features of these lines. (ii) What is an electromagnet and how is it made ?

  5. Question 5

    Magnetic Effects of Electric Current. This type asked 5 times: 2022, 2023, 2024, 2025, 2026. This one: 2026

    39 (A)
    (i) Draw a diagram showing the magnetic field lines around a bar magnet. Write any two characteristics of magnetic field lines. (ii) Write the statement of Right hand thumb rule. (iii) The concentric circles representing the magnetic field around a current carrying straight wire become larger and larger as we move away from the wire. How does magnetic field change on these concentric circles ?