# Uncertainty in Frequency of a Photon

1. Nov 10, 2008

### Quelsita

The question states:
consider a wave packet in the form of a pulse lasting 0.001sand length 3E5m. Since an individual photon of this wave can have an uncertainty of 3E5m (meanng it could be anywhere within the pulse), what is the uncertinty in momentum of the photon? in frequency?

OK, so using the equation $$\Delta$$p=h/$$\Delta$$x, I found the momentum to be 2.2E-39 kgm/s

I also have the equation $$\Delta$$v=$$\Delta$$E/h=1/$$\Delta$$t
but the answer is incorrect, how do you find the $$\Delta$$v for a single photon?

thanks!