Question

You set up an iron lightning rod. Its is 5.0 meters tall, with the top sharpened to a point and the bottom in good contact with the ground. You’ve determined that lightning bolts typically carry about 30,000 amps of current and last around 60 microseconds.

a. How much charge is delivered by a typical lightning bolt?

b. If you want the potential difference between the top and bottom of the lightning rod to be less than 120 V, what is the minimum radius of the rod?

Answer 1

Length, L = 5m, I = 30,000 A, 30,000 A, t = 60 li see (a) 30000 x 60 x 10-6 = 1.80 q: It (6) het r is the radius of red. V=120V resistivity of iron, Let Ris the resistance. P 9.7x10-0 sm slay R = 120 30000 4x1032 R =P se for el TR 9.7x10 x 5 3.14 x 4x1003 r² = 3.86 x 105 r: 6.2x107m r= 6.2mm .