# Question #18492

##### 1 Answer

#DeltaE_("vis") = (5.094 - 2.838) xx 10^(-19)color(white)(.)"J"#

#Deltanu_("vis") = (7.687 - 4.283) xx 10^(14)color(white)(.)"s"^(-1)" or Hz"# for the visible light range of

#390 - "700 nm"# .

**Visible light** is known to be in the region

The relationship between energy and frequency is given by the equation for **energy** **as quanta**,

#bb(E = hnu)# ,where

#h = 6.626 xx 10^(-34) "J"cdot"s"# is Planck's constant, and#nu# is the frequency of the light in#"s"^(-1)# .

And the relationship between frequency

#bb(nu = c/lambda)# ,with

#lambda# in#"m"# and#c = 2.998 xx 10^(8)# #"m/s"# .

Or, combined, we get

#bb(E = (hc)/lambda)# .

*lower wavelength bound* of **energy** of:

#E = (hc)/lambda = ((6.626 xx 10^(-34) "J"cdot"s")(2.998 xx 10^(8) "m/s"))/(390 xx 10^(-9) "m")#

#= ul(5.094 xx 10^(-19)color(white)(.)"J")#

Likewise, the *upper wavelength bound* of **range** shall be:

#color(blue)(barul|stackrel(" ")(" "DeltaE_("vis") = (5.094 - 2.838) xx 10^(-19)color(white)(.)"J"" ")|)#

*lower wavelength bound* of **frequency** of:

#nu = E/h = c/lambda#

#= (2.998 xx 10^(8) "m/s")/(390 xx 10^(-9) "m")#

#= ul(7.687 xx 10^(14)color(white)(.)"s"^(-1)" or Hz")#

Likewise, the *upper wavelength bound* of **range** shall be:

#color(blue)(barul|stackrel(" ")(" "Deltanu_("vis") = (7.687 - 4.283) xx 10^(14)color(white)(.)"s"^(-1)" or Hz"" ")|)#