Question 10
List three states in India where earthquakes are more likely to strike.
Three earthquake prone states in India are:
- Kashmir
- Gujarat
- Assam
Key Concepts Covered
This question tests your understanding of the following concepts from the chapter Some Natural Phenomena: Question, States, India, Earthquakes, Likely, Strike. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 8 curriculum.
A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This Question
Read the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to Remember
- Read the question carefully and identify all parts before answering.
- Use the terminology specific to this subject and chapter.
- Review the textbook content for this chapter before attempting questions.
- Practice writing concise, well-structured answers within time limits.
Practice more questions from Some Natural Phenomena — Science, Class 8 CBSE
Chapter Overview: Some Natural Phenomena
This chapter covers two major natural phenomena: lightning (caused by static electricity in clouds) and earthquakes (caused by tectonic plate movement). Key concepts include charging by rubbing, types of charges, electroscope, earthing, lightning conductor, seismograph, and Richter scale. Safety measures for both phenomena are practically important.
Board Exam Weightage: 5-7 marks | Difficulty: Moderate
Key Formulas & Concepts
| Concept | Details |
|---|---|
| Law of Charges | Like charges repel; unlike charges attract |
| Conservation of Charge | Total charge before and after rubbing remains the same (electrons transfer, not created) |
| Richter Scale | Logarithmic: each unit increase = 10 times more ground shaking |
| Lightning Conductor | Metal rod on building + copper wire + earth plate = safe path for lightning to ground |
Must-Know Concepts
- Charging by rubbing transfers electrons from one object to another (does not create charge)
- Glass rubbed with silk becomes positive; plastic rubbed with fur/wool becomes negative
- Electroscope detects charge: foil leaves diverge when charged
- Earthing provides a conducting path for excess charge to flow safely to the ground
- Lightning is a massive electrical discharge caused by charge build-up in clouds
- Earthquakes are caused by sudden movement of tectonic plates; measured on Richter scale
Lightning vs Earthquake
| Feature | Lightning | Earthquake |
|---|---|---|
| Cause | Charge build-up in clouds | Tectonic plate movement |
| Energy | Electrical | Mechanical (seismic waves) |
| Warning | Thunder, dark clouds | Usually no warning |
| Measurement | Not measured on standard scale | Richter scale / seismograph |
| Safety | Stay indoors, avoid tall objects/trees | Duck under table, move to open area |
Common Mistakes to Avoid
- Thinking rubbing creates new charges (it only transfers electrons)
- Confusing earthing and lightning conductor (conductor uses earthing principle)
- Thinking Richter scale is linear (it is logarithmic)
- Confusing epicentre (surface) and focus (underground)
Scoring Tips
- Learn safety rules for both lightning and earthquakes (frequently asked)
- Draw and label the electroscope and lightning conductor
- Remember: epi-centre is on top (epi = above), focus is underground
- Practice charge interaction problems: which attract, which repel
Frequently Asked Questions
Q: How many marks does this chapter carry in the exam?
A: Approximately 5-7 marks in the annual exam.
Q: What question types are commonly asked?
A: MCQs (1 mark), Very Short Answer (2 marks), Short Answer (3 marks), and Long Answer / Diagram (5 marks).
Q: Is this chapter important for competitive exams?
A: Yes, concepts from this chapter appear in NTSE, Olympiad, and other science competitions.