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(A) For the Lyman series,the wavelength is given by $\frac{1}{\lambda} = R \left( \frac{1}{1^2} - \frac{1}{n^2} \right)$ where $n = 2, 3, 4, \dots$. T

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$A$ is false,$B$ is true

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(A) For the Lyman series,the wavelength is given by $\frac{1}{\lambda} = R \left( \frac{1}{1^2} - \frac{1}{n^2} \right)$ where $n = 2, 3, 4, \dots$. The maximum wavelength (first line) is for $n=2$,$\lambda_{L,1} = \frac{4}{3R} \approx 121.6 \ nm$.For the Balmer series,the wavelength is given by $\frac{1}{\lambda} = R \left( \frac{1}{2^2} - \frac{1}{n^2} \right)$ where $n = 3, 4, 5, \dots$. The second spectral line is for $n=5$,$\lambda_{B,2} = \frac{1}{R(\frac{1}{4} - \frac{1}{25})} = \frac{100}{21R} \approx 434 \ nm$.Since $121.6 \ nm Statement $B$ is a fundamental postulate of the Bohr model,which states that $2\pi r = n\lambda$. Thus,statement $B$ is true.

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