Question: Storm clouds build up large negative charges, as described in the chapter. The charges dwell in charge centers, regions of concentrated charge. Suppose a cloud has -25 C in a 1.0-km-diameter spherical charge center located 10 km above the ground. The negative charge center attracts a similar amount of positive charge that is spread on the ground below the cloud.
The charge center and the ground function as a charged capacitor, with a potential difference of approximately 4.1Ã-108 V . The large electric field between these two "electrodes" may ionize the air, leading to a conducting path between the cloud and the ground. Charges will flow along this conducting path, causing a discharge of the capacitorâˆ'a lightning strike.
What is the approximate magnitude of the electric field between the charge center and the ground??
What is the approximate capacitance of the charge center + ground system?
If 12.5 C of charge is transferred from the cloud to the ground in a lightning strike, what fraction of the stored energy is dissipated?
If the cloud transfers all of its charge to the ground via several rapid lightning flashes lasting a total of 1 s, what is the average power?