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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 Ith = 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 Ith the value of emission current comes out to be about 0.1 A/cm2.

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