Class 8 Science Chapter 15 : Some Natural Phenomena
Class 8 Science Chapter 15 Some Natural Phenomena notes, MCQs, questions answers, lightning and earthquake safety for CBSE students.
Table of Contents
📝 Class 8 Science Chapter 15 CHAPTER NOTES
🔹 1. Natural Phenomena
Natural phenomena are events that occur naturally on the Earth due to natural forces.
Examples:
- Lightning
- Thunder
- Earthquake
🔹 2. Lightning
- Lightning is a natural electric discharge in the atmosphere.
- It occurs due to the accumulation of electric charges in clouds.
Process of Lightning:
- Clouds develop positive and negative charges.
- Opposite charges attract each other.
- Sudden discharge of electricity produces lightning.
🔹 3. Charging by Rubbing
- When two objects are rubbed together, they get electric charges.
- This is called charging by friction.
Example:
- Rubbing a plastic comb with dry hair.
🔹 4. Types of Charges
- Positive charge
- Negative charge
Rules:
- Like charges repel each other.
- Unlike charges attract each other.
🔹 5. Transfer of Charges
Charges can be transferred by:
- Conduction
- Induction
🔹 6. Dangers of Lightning
Lightning can:
- Kill humans and animals
- Damage buildings
- Cause fires
🔹 7. Lightning Safety
Do’s:
- Stay indoors
- Unplug electrical appliances
- Crouch low if outdoors
Don’ts:
- Do not stand under trees
- Do not use mobile phones outdoors
- Avoid open fields
🔹 8. Earthquake
- An earthquake is a sudden shaking of the Earth.
- It is caused by disturbance inside the Earth’s crust.
🔹 9. Seismic Zones
- Earth is divided into seismic zones based on earthquake risk.
- India has four seismic zones (II to V).
🔹 10. Richter Scale
- Used to measure the magnitude of earthquakes.
- It measures the energy released during an earthquake.
🔹 11. Safety During Earthquake
Inside buildings:
- Hide under a table
- Stay away from windows
Outside:
- Stay away from buildings, trees, and electric poles
❓ Class 8 Science Chapter 15 QUESTION–ANSWERS
🔹 Very Short Answer Questions (1 Mark)
Q1. What is lightning?
Ans: Lightning is a sudden electric discharge in the atmosphere.
Q2. Name the scale used to measure earthquakes.
Ans: Richter scale.
Q3. What are like charges?
Ans: Charges that repel each other are called like charges.
🔹 Short Answer Questions (2–3 Marks)
Q1. What causes lightning?
Ans: Lightning is caused by the accumulation and discharge of electric charges in clouds.
Q2. What is an earthquake?
Ans: An earthquake is a sudden shaking of the Earth caused by movement inside the Earth’s crust.
Q3. Mention two safety measures during lightning.
Ans:
- Stay indoors
- Avoid standing under trees
🔹 Long Answer Questions (5 Marks)
Q1. Explain lightning and its safety measures.
Ans:
Lightning is a natural electric discharge caused due to accumulation of electric charges in clouds. It can be very dangerous. During lightning, people should stay indoors, unplug electrical devices, avoid open fields, and not stand under trees to stay safe.
Q2. Describe earthquake safety measures.
Ans:
During an earthquake, people should stay calm, hide under sturdy furniture, stay away from windows, and avoid elevators. Outdoors, they should stay away from buildings, trees, and electric poles.
✅ Class 8 Science Chapter 15 MCQs – Chapter 15: Some Natural Phenomena
Choose the correct option
1. Lightning is caused due to:
A. Heat
B. Wind
C. Electric discharge
D. Rain
✅ Answer: C
2. Which scale measures earthquake magnitude?
A. Celsius scale
B. Richter scale
C. Kelvin scale
D. Beaufort scale
✅ Answer: B
3. Like charges:
A. Attract each other
B. Repel each other
C. Neutralize
D. Destroy each other
✅ Answer: B
4. Which is safe during lightning?
A. Standing under tree
B. Holding metal rod
C. Staying indoors
D. Standing in open field
✅ Answer: C
5. Earthquake occurs due to movement in:
A. Atmosphere
B. Oceans
C. Earth’s crust
D. Mantle only
✅ Answer: C
6. Which of the following is a natural phenomenon?
A. Fan
B. Lightning
C. Bulb
D. Heater
✅ Answer: B
7. Charging by rubbing is also called:
A. Induction
B. Conduction
C. Friction
D. Radiation
✅ Answer: C
8. India lies in how many seismic zones?
A. Two
B. Three
C. Four
D. Five
✅ Answer: C
9. During earthquake, one should:
A. Run upstairs
B. Use lift
C. Hide under table
D. Stand near window
✅ Answer: C
10. Which charge develops on clouds?
A. Only positive
B. Only negative
C. Both positive and negative
D. Neutral
✅ Answer: C