Townsend's Current Growth Equation by considering Secondary Ionization

Dear all, It is found that the video which I have published on 24/11/2019 has not been uploaded completely due to technical issues. Regret for my inconvenience and thanks for your support. So i have prepared modified video on the same topic ie 'Townsend's Current Growth Equation by considering Secondary Ionization'. Please watch this derivation and follow up. Thanks