Question

# 5. (10 points) You should now be comfortable with charge, current, voltage, power, and energy. A 12kA lightning bolt strikes an object directly for 15 us. Consider the following: a. How much charge is deposited on the object? How many electrons is this? b. c. If the lightning strike discharges across a voltage potential of 250 million volts, what is the lightning bolt's power? Express your answer in the units of gigawatts (GW). How much energy is imparted by the lightning strike? d. e. A typical cell phone battery has a charged capacity of 1800 mAh at 3.7 V. If the energy from the lightning strike were harnessed, how many cell phone batteries could be fully charged using this energy? Note: It is common to use an ampere-hour (Ah) or milliampere-hour (mAh) as a measure of charge storage capacity. One mAh is the charge delivered by a one milliamp current for one hour. Without a stated voltage, however, this doesn't tell us how much energy a battery can store. For this, energy storage is typically rated in watt-hours (Wh); a smartphone battery has a storage capacity of ~5 Wh.  Fig: 1