The wavelength of the first spectral line of the Lyman series of the hydrogen spectrum is:
1. \(1218~\mathring A\)
2. \(974.3~\mathring A\)
3. \(2124~\mathring A\)
4. \(2120~\mathring A\)

In which of the following systems will the wavelength corresponding to \(n=2\) to \(n=1\) be minimum?

The ratio of wavelengths of the last line of the Balmer series and the last line of the Lyman series is:
1. \(1\)
2. \(4\)
3. \(0.5\)
4. \(2\)

The transition from the state \(n=3\) to \(n=1\) in hydrogen-like atoms results in ultraviolet radiation. Infrared radiation will be obtained in the transition from:
1. \(3\rightarrow 2\)
2. \(4\rightarrow 2\)
3. \(4\rightarrow 3\)
4. \(2\rightarrow 1\)

Which of the following transitions will the wavelength be minimum?
1. \(n=5~\text{to}~n=4\)
2. \(n=4~\text{to}~n=3\)
3. \(n=3~\text{to}~n=2\)
4. \(n=2~\text{to}~n=1\)