PYQ Vault

Day 55: CBSE Class 10 Science

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

  1. Question 1

    Light — Reflection and Refraction. This type asked 3 times: 2024, 2025, 2026. This one: 2026

    35
    (a) State the laws which help to find out the angle of incidence and angle of reflection in the ray diagram given above. (b) Find out the angle of incidence and angle of reflection in the given ray diagram.

  2. Question 2 (case study, 4 parts)

    Light — Reflection and Refraction. This type asked 3 times: 2023, 2024, 2026. This one: 2026

    Lenses can form different types of images depending upon their focal length and position of object. A convex lens can create real, inverted or virtual, erect images, while a concave lens forms only virtual and diminished images. The focal length determines the power of lens. Convex lenses have positive focal length while concave lenses have negative focal length by convention. When lenses are placed together, their combined power is determined by the sum of their individual powers. Ray diagrams help to visualize how light converges or diverges through lens to form an image.
    38 (a)
    A convex lens of focal length 20 cm is used to form an image. If an object is placed at 40 cm from the lens, what will be the position and nature of image ?
    38 (b)
    Illustrate the formation of image with the help of ray diagram, when the object is placed between the optical centre and principal focus of concave lens.
    38 (c) (i)
    A lens combination consists of a convex lens of focal length 30 cm and a concave lens of focal length 15 cm placed together. Find the equivalent focal length and power of this lens combination.
    38 (c) (ii)
    Two lenses are placed in contact. One is a concave lens with focal length 2 m and the other is a convex lens with focal length 1.5 m. What type of lens will the combination behave as (convex or concave) ? Give reason.

  3. Question 3

    Magnetic Effects of Electric Current. This type asked 3 times: 2023, 2025, 2026. This one: 2026

    37
    (a) The pattern of magnetic field due to a current carrying wire depends upon the shape made by that wire. Justify. (b) A current carrying straight wire AB is shown in the given diagram. Out of X, Y and Z on which point will the strength of magnetic field be maximum and why ?

  4. Question 4

    Magnetic Effects of Electric Current. This type asked 3 times: 2023, 2024, 2026. This one: 2026

    39 (b)
    (i) With the help of a diagram, show that a current-carrying conductor placed in an external magnetic field, experiences a force. Indicate the direction of the field, current and force clearly. (ii) The diagram given below shows an electron moving in a uniform magnetic field. (I) What will be the direction of the force acting on the electron ? (II) What will happen to the direction of the force acting on the electron, if the direction of the magnetic field as well as the direction of motion of the electron, both are reversed ?

  5. Question 5

    Magnetic Effects of Electric Current. This type asked 3 times: 2023, 2024, 2026. This one: 2026

    39 (B)
    (i) Why is fuse an important component in our electric circuits ? (ii) Distinguish between overloading and short-circuiting of a circuit. (iii) Giving reason explain what type of materials are used in fuse wires.