9.2 Resistance

The photograph shows a statue of Buddha in Sri Lanka, which is protected by a lightning conductor.

During a storm, a potential difference of 2.7 MV was generated between a cloud and the top of the lightning conductor on the statue. A flash of lightning passed between the cloud and the lightning conductor, producing a current of 25 kA for a time of 7.5 ms.

Calculate the energy transferred by the lightning strike.

Energy transferred = ............................................

The lightning conductor is made from copper.  

Sketch an I–V graph for the rod when it conducts a lightning strike to earth

Explain any changes which the lightning rod would undergo during a lightning strike.