The ionisation energies of K-shell for cobalt, copper, and molebdenum are 7.8, 9.0 and `20.1 KeV`
Channel: Doubtnut
Date: 26/01/2020

The ionisation energies of K-shell for cobalt, copper, and molebdenum are 7.8, 9.0 and `20.1 KeV` respectively. If any metal out of these is used as target in an X-ray tube operated at `15KV`, then (a) the K-series of characteristic X-rays will be emitted only by cobalt (b) the K-series of characteristic X-rays will be emitted only by cobalt & Cu (c) the K-series of characteristic X-rays will be emitted only by cobalt, Cu , Co and Mo (d) the minimum wavelength of continuous X-rays emitted by the three metals will be same