Question

how many photons of light having a wavelength 4000 armstrong are necessary to provide 1.00J of energy?

Answer 1

@Preetha

Answer 2

@Frostbite

Answer 3

I think you mean angstroms. So first you have to find the frequency of the photons

\[frequency=C/\]
3.00*10^8 / 4*10^-7= 7.5*10^14 Hz
Then you can find the energy of one photon
Energy=h*frequency

So
6.62*10^-34 * 7.5*10^14= 5.0*10^-19 J

So then 1.00J / 5.0*10^-19= 2.0*10^18 photons

Answer 4

frequency=C/lambda

Answer 5

4000 angstroms is equal to 4*10^-7 M