Explain the process that causes lightning.
Lightning is caused by the buildup and sudden discharge of electric charges in clouds.
During a storm, strong winds blow upwards and downwards, causing water droplets and ice particles to rub against each other. This rubbing creates static electric charges within the clouds.
Positively charged lighter ice particles move upwards to the upper part of the clouds, while negatively charged heavier water droplets occupy the lower part, creating charge separation.
When the negatively charged lower part of the cloud comes near the ground, it causes the ground and nearby objects to become positively charged.
Normally, air acts as an electrical insulator and prevents opposite charges from meeting. However, when the charge buildup becomes very large, the insulating property of air breaks down.
A sudden flow of charges occurs between opposite charges—either within a cloud, between clouds, or between a cloud and the ground—producing a bright flash of light called lightning.
Explanation
The chapter describes lightning formation in Section 6.5, explaining charge separation through rubbing, the role of air as an insulator, and the sudden discharge that creates the lightning flash.
Solution Steps
Lightning is caused by the buildup and sudden discharge of electric charges in clouds
Strong winds cause water droplets and ice particles to rub against each other, creating static electric charges
Positively charged lighter ice particles move upward while negatively charged heavier water droplets occupy the lower part, creating charge separation
The negatively charged lower part of the cloud induces positive charge on the ground and nearby objects
Air normally acts as an electrical insulator but breaks down when charge buildup becomes very large
Sudden flow of charges occurs between opposite charges, producing the bright flash of light called lightning