Question

The maximum electron current per unit area provided by an emitter is given by (where J = current density, T = absolute temperature in K, ɸ = work function in keV, k = Boltzmann’s constant & A=emission constant)

a.

J = AT exp(-ɸ/kT)

b.

J = AT (-ɸ/kT)

c.

J = AT² exp(-ɸ/kT)

d.

J = exp(-Aɸ/kT²)

Answer: (c).J = AT² exp(-ɸ/kT)

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Q. The maximum electron current per unit area provided by an emitter is given by (where J = current density, T = absolute temperature in K, ɸ = work function in keV, k = Boltzmann’s...

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