SZF IOS 2023 previous year paper practice · PYQ-pattern set

SZF IOS 2023 PYQ-pattern questions

Showing 10 of the 19 PYQ-pattern questions in this set — freshly worded in that year's pattern, not the original questions. Answers and solutions open under each question.

1. Q1 · Gravitation

   The value of acceleration due to gravity on the surface of the Moon is approximately one-sixth of that on Earth. If an object weighs 60 N on Earth, what will be its weight on the Moon?

   • A. 10 N
   • B. 6 N
   • C. 12 N
   • D. 360 N
   Answer and solution

   Answer: A

   Weight on Moon = Weight on Earth × (1/6) = 60 × (1/6) = 10 N.

2. Q2 · Electricity

   A current of 0.5 A flows through a conductor for 2 minutes. How much charge passes through the conductor in this time?

   • A. 30 C
   • B. 60 C
   • C. 90 C
   • D. 120 C
   Answer and solution

   Answer: B

   Charge Q = I × t = 0.5 A × 120 s = 60 C.

3. Q3 · Acids, Bases and Salts

   What is the pH value of pure water at 25°C?

   • A. 0
   • B. 7
   • C. 14
   • D. 10
   Answer and solution

   Answer: B

   Pure water at 25°C has a pH of 7, indicating it is neutral (neither acidic nor basic).

4. Q4 · Periodic Classification

   An element X has atomic number 12. What will be its position in the periodic table?

   • A. Group 2, Period 3
   • B. Group 1, Period 3
   • C. Group 2, Period 2
   • D. Group 3, Period 2
   Answer and solution

   Answer: A

   Element with atomic number 12 has electronic configuration 2,8,2 with 2 valence electrons (Group 2) and 3 shells (Period 3), placing it in Group 2, Period 3.

5. Q5 · Natural Resources

   The percentage of nitrogen gas in the Earth's atmosphere is approximately:

   • A. 21%
   • B. 78%
   • C. 0.03%
   • D. 50%
   Answer and solution

   Answer: B

   Nitrogen makes up approximately 78% of Earth's atmosphere, making it the most abundant gas, followed by oxygen at about 21%.

6. Q6 · Control and Coordination

   Which plant hormone is responsible for inhibiting growth and causing wilting of leaves during water stress conditions?

   • A. Auxin
   • B. Gibberellin
   • C. Abscisic acid
   • D. Cytokinin
   Answer and solution

   Answer: C

   Abscisic acid (ABA) is known as the stress hormone, which promotes stomatal closure during drought and inhibits growth to conserve water.

7. Q7 · Non-Verbal Reasoning

   A cube is painted red on all faces. It is then cut into 64 smaller identical cubes. How many of the smaller cubes will have exactly two faces painted?

   • A. 8
   • B. 12
   • C. 24
   • D. 32
   Answer and solution

   Answer: C

   When a cube is cut into 64 smaller cubes, it is divided into 4×4×4. Cubes with exactly two painted faces lie on the edges (but not corners): 12 edges × 2 cubes per edge = 24 cubes.

8. Q8 · Higher Order Thinking

   If all living organisms require water to survive, and cacti are living organisms that thrive in deserts with minimal rainfall, what is the most logical explanation?

   • A. Cacti do not actually need water to survive
   • B. Cacti have adaptations to store and conserve water efficiently
   • C. Desert rainfall is actually higher than commonly believed
   • D. Cacti obtain all their water from underground rivers
   Answer and solution

   Answer: B

   The logical conclusion reconciling both facts is that cacti have special adaptations like thick stems for water storage, waxy coatings to reduce evaporation, and deep roots, allowing survival with minimal water.

9. Q9 · Experimental and Lab-based

   A student wants to determine which type of soil (sand, clay, or loam) retains water best. What should be measured after pouring equal amounts of water into each soil sample?

   • A. The color change in each soil type
   • B. The amount of water drained out from each sample
   • C. The temperature of each soil sample
   • D. The weight of the container holding the soil
   Answer and solution

   Answer: B

   Measuring the drained water shows how much water passed through versus how much was retained. Less drainage indicates better water retention capacity.

10. Q10 · Light — Reflection and Refraction

    A concave mirror has a focal length of 20 cm. An object is placed 30 cm from the mirror. What is the nature and position of the image formed?

    • A. Real, inverted, at 60 cm from the mirror
    • B. Virtual, erect, at 60 cm from the mirror
    • C. Real, inverted, at 15 cm from the mirror
    • D. Virtual, erect, at 30 cm from the mirror
    Answer and solution

    Answer: A

    Using mirror formula 1/f = 1/v + 1/u: 1/20 = 1/v + 1/(-30), solving gives v = 60 cm. Since v is positive, the image is real and inverted.