Question

Question #f7f0b

Answer 1

I got: `1.7xx10^18` photons

Explanation:

We know that the energy of a photon is given by Einstein's relationship:

`E=hf`

where:
`f=` frequency;
`h=6.63xx10^-34Js` is Planck's Constant.

To find frequency we can use:

`c=lambdaf`

Where:
`lambda=583xx10^-9m` is wavelength;
`c=3xx10^8m/s` is the speed of light in vacuum.

So we get:

`f=c/lambda`

and

`E=hc/lambda=6.63xx10^-34*(3xx10^8)/(583xx10^-9)=3.41xx10^-19J` for one photon at this specific eavelength.

so in `0.576J` we have:

`0.576/(3.41xx10^-19)=1.68xx10^18~~1.7xx10^18` photons