Question

Question 4 of 25 Submit What is the wavelength of a photon if the energy is 7.27 x 10-19 J? (h = 6.626 x 10-34 J·s) | nm x | 1 4 ( 7 2 5 8 3 6 9 +/- x 100

Answer 1

We know that Energy of a photon is given as

$E=\frac{hc}{\lambda}$=7.27 x 10^-19 J

Where h=Planck's constant=6.626x10^-34 J-s

c=speed of photon=speed of light=3x10⁸ m/s

$\lambda$=wavelength of photon

Substitute the values for energy, h, and c in above equation we get

7.27 x 10^-19 J=(6.626 x 10^-34 J-s x 3 x 10⁸ m/s)/$\lambda$

$\lambda$=6.626 x 10^-34 J-s x 3 x 10⁸ m/s)/(7.27 x 10^-19 J)

=2.734 x 10^-7 m

=2.734 x 10^-9 x 10⁹ x 10^-7 m (multiply with 10^-9 x 10⁹)

=2.734 x 10^-9 x 100 m

=273.4 x 10^-9 m=273.4 nm (1 nm=10^-9 m)

So the wavelength of the photon is 273.4 nm