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You\\'ve decided to protect your house by placing a6.6-mm-tall iron lightning rod next to the house. The top is sharpened to a point and the bottom is in good contact with the ground. From your research, you\\'ve learned that lightning bolts can carry up to 47kA kA of current and last up to 50 uSμs.

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How much charge is delivered by a lightning bolt with these parameters?

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You don\\'t want the potential difference between the top and bottom of the lightning rod to exceed 170 V

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V

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. What minimum diameter must the rod have?

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Step 1:

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The lightning bolts carry upto 47kA.

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The lightning last upto $\"\"$ .

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Find the charge delivered by the lightning bolt.

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Current across a cinductor $\"\"$ .

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$\"\"$

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$\"\"$

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Charge delivered by the lightning bolt is 2.35 C.

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Step 2:

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Find the diameter of the lightning rod.

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Potential difference: $\"\"$ .

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Resistivity of the material: $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Diameter of the lightning rod is 1.43 cm.

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Solution:

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Charge delivered by the lightning bolt is 2.35 C.

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Diameter of the lightning rod is 1.43 cm.

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