Physics · Electrostatic Potential
हिन्दीGiven below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): A practical capacitor designed with a capacitance of \( 1\text{ F} \) with plate separation of \( 1\text{ cm} \) in vacuum requires plate dimensions comparable to a small city. Reason (R): The permittivity of free space \( \varepsilon_0 \) is extraordinarily large in SI units. In the light of the above statements, choose the correct answer from the options given below:
Correct answer · Option 3
is true but (R) is false.
Explanation
Assertion is true because \( A = Cd/\varepsilon_0 \approx 10^9\text{ m}^2 \) (a plate of \( 30\text{ km} \times 30\text{ km} \)). Reason is false because \( \varepsilon_0 = 8.85 \times 10^{-12}\text{ F/m} \), which is extremely small, not large.