Given below are two statements: A: The outer body of an air craft is made of metal which protects persons sitting inside from lightning-strikes. R: The electric field inside the cavity enclosed by a conductor is zero.

 

⚡ Question

Given below are two statements:

Assertion (A):
The outer body of an aircraft is made of metal which protects persons sitting inside from lightning strikes.

Reason (R):
The electric field inside the cavity enclosed by a conductor is zero.

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🖼️ Question Image

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✍️ Short Solution

Step 1 — Understanding the concept

When a conductor is placed in an external electric field (like a thundercloud’s field), charges on its surface rearrange themselves such that the net electric field inside becomes zero.

This is a direct result of electrostatic shielding — a fundamental property of conductors.

Step 2 — Applying to the aircraft

The metal body of the aircraft acts as a closed conducting shell (essentially a Faraday cage).

• Any external electric field (from lightning or thunderclouds) causes charge redistribution only on the outer surface.

• The field inside the cabin (the cavity) remains zero, keeping passengers completely safe from the electric discharge.

Step 3 — Checking the statements

• Assertion (A): ✅ True — The metal body indeed protects passengers from lightning.

• Reason (R): ✅ True — The electric field inside a cavity enclosed by a conductor is zero.

• Explanation link: Reason (R) correctly explains Assertion (A).

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🧠 Concept Recap

Concept	Explanation
Electrostatic Shielding	Phenomenon by which a conducting shell prevents external electric fields from affecting its interior.
Faraday Cage	A hollow conductor that blocks electric fields — examples include cars, airplanes, and metal rooms.
Electric Field inside Conductor	Always zero in electrostatic equilibrium.

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🖼️ Image Solution

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✅ Final Answer

$$\boxed{{\displaystyle \text{Both A and R are true, and R is the correct explanation of A.}}}$$

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🎯 Key Takeaway

The metal body of an aircraft works as a Faraday cage, providing electrostatic shielding and ensuring passenger safety even during lightning strikes ⚡✈️