the wavelength range of the visible spectrum extends from violet ( 400 nm) to red ( 750 nm). Express these wavelengths in frequencies (Hz) . (1nm =` 10 ^(-9)m`)

Explanation

Wavelength of violet light = 400 nm
`= 400xx10^(-9) m ( 1 nm = 10 ^(-9) m)`
Frequncy ` (v) -=(c ) /( lamda) = ( 3 x10^(8) ms^(-1))/(400xx10^(-9) m)`
`=7.50 xx 10^(-9) m`
` v=(c )/(lamda) = ( 3xx 10^(8) ms^(-1))/ 750 xx 10^(-9) m`
` v= 4.0 xx10^(14) Hz`
The range of visible spectrum of from `4.0xx10^(14) Hz` to `7.5 xx 10^(14)` Hz in terms of frequency units