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

Taking the second part first, the visible spectrum is about $400 - 800$ $n m$, and this is longer than that, so it is infrared.
The energy is given by $E = \frac{h c}{\lambda}$ with $\lambda$ measured in metres.
$E = \frac{h c}{\lambda} = \frac{6.63 \times {10}^{-} 34 \times 3 \times {10}^{8}}{1.5 \times {10}^{-} 6} = 1.33 \times {10}^{-} 19$ $J$