Electromagnetic waves of frequency \( 5 \times 10^{14} \, {Hz} \) lie in the visible spectrum. The visible region of the electromagnetic spectrum typically spans frequencies from \( 4 \times 10^{14} \, {Hz} \) to \( 7.5 \times 10^{14} \, {Hz} \).
Therefore, \( 5 \times 10^{14} \, {Hz} \) is in the visible region.
Hence, the correct answer is (C).
Calculate the wavelength of the first two lines in the Balmer series of the hydrogen atom.