If a photon has an energy of 8.6 x 10-19 J, what will be its wavelength (in nm)? Show all calculations leading to an answer.

Question

If a photon has an energy of 8.6 x 10-19 J, what will be its wavelength (in nm)?  Show all calculations leading to an answer.

anonymous · Answer

I really need help

whpalmer4 · Answer

$$E = h f$$$$c = f\lambda$$$$h \approx 6.626*10^{-34}\text{ J s}$$$$c = 299792458 \text{ m/s}$$
Solve the first equation for $f$ in terms of $c$ and $\lambda$
Solve the second equation for $\lambda$, and substitute the expression you got for $f$ in place of $f$.  Plug in your energy and the values I gave for $h$ and $c$.  This will give you the wavelength in meters.  Convert that to nanometers and you've got your answer.

Your answer should be between 100 and 1000 nm.