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Question
Lightning is a very good example of a natural current. In typical lightning, there is 109 J energy transfer across the potential difference of 5 × 107 V during a time interval of 0.2 s. Using this information, estimate the following quantities:
- the total amount of charge transferred between cloud and ground
- the current in the lightning bolt
- the power delivered in 0.2 s.
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Solution
Given data: E = 109J, V = 5 × 107 V, t = 0.2s
(a) Total amount of charge-
W = qv `=> "q" = "W"/"V" = "E"/"V" = 10^9/(5 xx 10^7) = 0.2 xx 10^2`
q = 20 C
(b) current, I = `"q"/"t" = 20/0.2 = 200/2 = 100`
I = 100 A
(c) Power, P = VI = `5 xx 10^7 xx 100 = 5 xx 10^9`
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