The wavelength of light is given by the velocity divided by the frequency. The velocity of blue light is 300,000,000 m/sec, and its frequency is…. The wavelength of light is given by the velocity divided by the frequency. The velocity of blue light is 300,000,000 m/sec, and its frequency is 650,000,000,000,000 cycles per second. What is the wavelength of blue light? Use scientific notation to make your calculation and express your answer