Earth Solar System and Environment (Class 4)

What this worksheet covers

This is a fifteen-question practice worksheet on earth, solar system and our environment for Class 4, written to the pattern of the SOF National Science Olympiad (NSO). It carries 21 marks and is designed to be attempted in 40 minutes, split across three sections — Scientific Reasoning, Applying What You Know and Achievers Section. Every question is multiple choice with exactly one correct option, and every one comes with a fully worked solution rather than just an answer key — so a child who gets one wrong can see where the reasoning went astray instead of only learning that it did.

Skills your child practises

• Applied problem-solving on earth, solar system and our environment at Class 4 level
• Working accurately against a time limit, as the real paper demands
• Scientific Reasoning questions in the olympiad format
• Applying What You Know questions in the olympiad format
• Achievers Section questions in the olympiad format
• Reading worked solutions to find the step that went wrong

How to use it

1. 1There are 15 questions in this worksheet. All questions are compulsory.
2. 2Each question has four options (A), (B), (C) and (D). Exactly one option is correct.
3. 3Questions 1–12 carry 1 mark each. Questions 13–15 (Achievers Section) carry 3 marks each.
4. 4There is no negative marking. Study every diagram and table carefully.

Sample questions from this worksheet

A preview of what's inside Earth Solar System and Environment (Class 4) — the PDF has the full set, and every question comes with a worked solution like these.

1. 1. How many planets are there in our solar system?

   • ASeven
   • BTen
   • CNine
   • DEightcorrect
   Solution: There are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Pluto was reclassified as a dwarf planet in 2006.

2. 2. An astronaut who weighs 60 kg-wt on the earth would weigh only about 10 kg-wt on the moon. This is because the moon _______.

   • AHas no gravity at all
   • BHas no air
   • CIs much colder than the earth
   • DHas a much weaker pull of gravity than the earthcorrect
   Solution: The moon is far smaller and lighter, so its gravitational pull is only about one-sixth as strong. Weight is the pull of gravity, so it falls to about 60 ÷ 6 = 10. The astronaut's mass is unchanged, and the moon does have gravity — it is simply weaker.

3. 3. Consider the following statements.(i) The moon produces its own light.(ii) The sun is the nearest star to the earth.(iii) Deforestation increases the amount of carbon dioxide in the air.Which of the statements is/are correct?

   • A(i) and (ii) only
   • B(ii) and (iii) onlycorrect
   • C(i) and (iii) only
   • DAll three
   Solution: Statement (i) is false — the moon has no light of its own and merely reflects sunlight. Statement (ii) is true; the sun is about 150 million km away, while the next nearest star is thousands of times further. Statement (iii) is true; trees absorb carbon dioxide, so cutting them down leaves more of it in the air. Hence (ii) and (iii).