phtoelectron are emitted when `4000A^(0)` radiation is incident on a surface of work fuction `
Channel: Doubtnut
Date: 2020-02-16

phtoelectron are emitted when `4000A^(0)` radiation is incident on a surface of work fuction `1.9eV`. these photoelectrons pass through a region has a- particles to form `He^(+)` ion, emitting a single photon in this process `He^(+)` ions thus formed are in their fourth excited state. Energy of emitted photon in range of `3eV` & `4eV` after combination is