Question

Given a wavelength of 1500 nanometers, how much energy does the wave have? What type of radiation would this wave be?

Answer 1

Taking the second part first, the visible spectrum is about `400-800` `nm`, and this is longer than that, so it is infrared.

The energy is given by `E=(hc)/lambda` with `lambda` measured in metres.

`E=(hc)/lambda=(6.63xx10^-34xx3xx10^8)/(1.5xx10^-6)=1.33xx10^-19` `J`