In order to obtain spectrum from the emitted radiation, the atomic gas or vapour must be excited at a) much less than atmospheric pressure b) much high than atmospheric pressure c) atmospheric pressure d) high pressure and temperature

In order to obtain spectrum from the emitted radiation, the atomic gas or vapour must be excited at
a) much less than atmospheric pressure b) much high than atmospheric pressure
c) atmospheric pressure d) high pressure and temperature
by

1 Answer

Answer :

a) much less than atmospheric pressure
by

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