The correct option is (c) 1 and 3 only.
Explanation
Lightning is a massive electrostatic discharge caused by the imbalance of electric charges within the atmosphere. It involves the buildup of static electricity and the subsequent breakdown of the insulating properties of air.- Statement 1 is Correct: Lightning is caused by the accumulation of electric charges in clouds. During the development of a thunderstorm, air currents move upward while water droplets move downward. This friction and interaction cause a separation of charges, typically resulting in positive charges accumulating near the upper edges of the clouds and negative charges accumulating near the lower edges.
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Statement 2 is Incorrect: The process of electric discharge is not limited to interactions between two clouds. Discharge can occur:
- Within a single cloud (Intra-cloud).
- Between two different clouds (Inter-cloud).
- Between a cloud and the ground (Cloud-to-ground).
- Statement 3 is Correct: Under normal conditions, air is a poor conductor of electricity (an insulator). However, when the magnitude of the accumulated charge becomes very large, the electric field becomes strong enough (approximately \(3 \times 10^6\) V/m) to strip electrons from air molecules. This process, known as dielectric breakdown, turns the air into a conductive plasma, allowing electricity to flow as lightning.
Key Takeaway: Lightning is an electric discharge resulting from charge accumulation in clouds. It occurs when the electric field exceeds the dielectric strength of air, causing normally insulating air to conduct electricity between clouds or between a cloud and the earth.