`(1)/(2)m_(1)v_(1)^(2)=qV` तथा `(1)/(2)m_(2)v_(2)^(2)=qV`
`:.m_(1)v_(1)^(2)=m_(2)v_(2)^(2),R=(mv)/(qB)`
`(R_(1))/(R_(2))=(m_(1)v_(1))/(m_(2)v_(2))` या `(R_(1)^(2))/(R_(2)^(@))=(m_(1)^(2)v_(1)^(2))/(m_(2)^(2)v_(2)^(2))=(m_(1)xxm_(1)v_(1)^(2))/(m_(2)xxm_(2)v_(2)^(2))`