Assertion (A): At a temperature of 1000 K, thermionic emission current is about

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Question
Assertion (A): At a temperature of 1000 K, thermionic emission current is about 0.1 A/cm² of surface.
Reason (R): Thermionic emission current is given by I_th = SA₀ T² e^-Ew/kT.
Options
A. Both A and R are true and R is correct explanation of A
B. Both A and R are true but R is not correct explanation of A
C. A is true but R is false
D. A is false but R is true

Correct Answer

Both A and R are true and R is correct explanation of A

Explanation

If different values are substituted in the equation for I_th the value of emission current comes out to be about 0.1 A/cm².

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