Question

What is the order of the electric field required for field emission?

Options

• \[10^{-8}\,\mathrm{V\,m^{-1}}\]

• \[10^{8}\,\mathrm{V\,m^{-1}}\]

• \[1\,\mathrm{V\,m^{-1}}\]

• \[1.602\times10^{-19}\,\mathrm{V\,m^{-1}}\]

Answer 1

Field emission requires a very high electric field, of the order of \[10^{8}\,\mathrm{V\,m^{-1}}\]. This field can pull electrons out of the metal.