An average bolt of negative lightning (lightning composed of electrons) goes from cloud to ground and carries a current of 40 kA. The typical charge transferred is five coulombs. The typical lightning bolt delivers 5 x 108 J of energy to the ground.
a) Calculate the average time of a lightning strike.
b) Calculate the average number of electrons transferred from cloud to ground.
c) The average potential difference between cloud and ground is 1 x 1010 V before a lightning discharge. Which side is at the higher potential?
d) What is the magnitude and direction of the electric field in the 'cloud-ground' capacitor before its discharge?
e) Assume a lightning bolt travels straight towards the ground through a region of air where the earth's magnetic field is directed from north to south and parallel to the ground and of magnitude 50 x 10-6 T. What is the direction of deflection of the lightning bolt from straight down? I.e. is it east, south, north or west?
f) Assume an average lightning bolt were to simultaneously strike the tops of two identical 10-m flag poles spaced 2 m apart. Calculate the current through each flag pole.
g) Calculate the magnitude and direction of the magnetic force between these flag poles during the strike.