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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The outer body of an air craft is made of metal which protects persons sitting inside from lightning-strikes. Reason (R) : The electric field inside cavity enclosed by a conductor is zero. In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
2. (A) is correct but (R) is not correct
3. Both (A) and (R) are correct and (R) is the correct explanation of (A)
4. (A) is not correct but (R) is correct

Correct answer: Both (A) and (R) are correct and (R) is the correct explanation of (A)

Solution

The assertion is correct because the metal body of an aircraft acts as a Faraday cage, protecting occupants from lightning strikes. The reason is also correct, as it explains that the electric field inside a conductor is zero, which is why the interior of the aircraft remains safe during a lightning event.

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