SINDH PUBLIC SERVICE COMMISSION, HYDERABAD
COMBINED COMPETITIVE EXAMINATION, 2023
GENERAL SCIENCE & ABILITY.
Friday 18th April, 2025
Time. 09:00 am to 12:00 Noon
Maximum Marks.100
Note: Attempt Five questions by selecting at least two questions from Section-I and two questions from Section-II. All questions carry equal marks.
Question No.
Marks
SECTION-I
01 (i) Why does the sky appear blue during the day but red or orange during sunrise and sunset? 05
(ii) What causes tides in the ocean? 05
(iii) What is a Supernova? 05
(iv) What are stars mostly made of? What makes the stars to emit light and heat? 05
02 Give the scientific explanations of the following:
(i) When an injury occurs, how does clotting take place? 05
(ii) Why do we need to sleep? 05
(iii) What makes our bones strong? 05
(iv) Why do we sweat? 05
03 (i) Why metals are shiny in nature? Please explain. 10
(ii) What properties give the ductility in metal? 10
04 (i) Write the photosynthesis equation and explain the process? 10
(ii) In which form glucose is stored and in which part(s) of a plant? 05
(iii) Why the plants appear green to us? 05
05 (i) How ozone layer is formed? 05
(ii) Does ozone layer regenerate? If yes, then explain. 10
(iii) What are the harmful effects of ozone layer depletion on human health? 05
SECTION-II
06 Define and give features of sustainable development. What are the successes of the environmental movement? (20 Marks)
07 (A) What is the next number in the following series:
2 11 18 23 ———— (05 Marks)
(B) Identify the following Mathematical symbols: (05 Marks)
(i) ⊆
(ii) ≡
(iii) ∴
(iv) ∈
(v) Lxii
(C) A batsman scored 110 runs which included 3 boundaries and 8 sixes. What percentage of his total score did he make by running between the wickets? (10 Marks)
08 (A) What should come in place of both x in the equation x/128 = 162/x (10 Marks)
(B) In a mixture of 60 litres, the ratio of milk and water is 2 : 1. If this ratio is to be 1:2, then how much quantity of water in litres to be added further? (10 Marks)
09 (A) Describe key properties of Prime numbers, Co prime numbers, Rational numbers, Natural numbers and Composite numbers. (10 Marks)
(B) Six bells commence tolling together and toll at intervals of 2, 4, 6, 8, 10 and 12 seconds respectively. In 30 minutes, how many times do they toll together? (10 Marks)
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