The picture below shows the tower and spire of the library of Lincoln College, Oxford. If you can magnify the picture, you'll see that there is a lightning conductor going from the point at the top and then down the tower, to the left of the window, until it reaches the ground. You need to look up the material used to make lightning conductors, and its resistivity. Then you'll need to estimate the length of the lightning conductor and the dimensions needed to calculate the cross-sectional area. The two close-up photographs below will help with this. CALCULATE THE RESISTANCE OF THE LIGHTNING CONDUCTOR AND JUSTIFY THE SIZES THAT YOU HAVE ESTIMATED.
Estimation is an important skill in Physics and Engineering.
