Science · Class 8
Some Natural Phenomena
Lightning, earthquakes, and safety measures.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Lightning is electric discharge between clouds or cloud and ground. Earthquakes are vibrations of Earth's crust. This chapter covers causes, measurement, and safety measures.
Lightning
- Charges build up in clouds — separation of + and −
- Lightning conductor protects buildings — copper rod to ground
- Thunder follows lightning — sound travels slower than light
Earthquakes
- Caused by sudden movement of tectonic plates
- Epicentre: point on surface above focus
- Richter scale measures magnitude; seismograph records waves
Safety
- During lightning: stay indoors, avoid trees/water/open fields
- During earthquake: under sturdy table, stay away from windows
- Secure heavy furniture; emergency kit ready
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Lightning safety
Why shouldn't you stand under a tree in lightning?
- 1Tree may be tallest point
- 2Lightning seeks easy path to ground
- 3Can strike tree and pass to you
Answer
Tree attracts lightning strike
Earthquake waves
What does seismograph record?
- 1Vibrations of ground during earthquake
- 2Helps locate epicentre
- 3Richter scale from wave amplitude
Answer
Ground motion during quake
Key Points to Remember
- ✓ Tsunami follows undersea earthquakes
- ✓ Fault zones prone to earthquakes
- ✓ Do not use lifts during earthquake
Exam Tips
- • Draw lightning conductor on building
- • Explain Richter scale
- • List do's and don'ts during earthquake
Practice MCQs — Some Natural Phenomena
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Lightning is: