Question

Human vision cuts off on the red side of the spectrum at about 675 nm. What is the energy of a photon (in J) of this wavelength?

Answer 1

The energy of a photon is 2.94x10⁻¹⁹ J.

Step-by-step explanation:

The energy of the photon is given by:

`E = (hc)/(\lambda)`

Where:

h: is Planck's constant = 6.62x10⁻³⁴ J.s

c: is the speed of light = 3.00x10⁸ m/s

λ: is the wavelength = 675 nm

Hence, the energy is:

`E = (hc)/(\lambda) = (6.62 \ccdot 10^(-34) J.s*3.00 \cdot 10^(8) m/s)/(675 \cdot 10^(-9) m) = 2.94 \cdot 10^(-19) J`

Therefore, the energy of a photon is 2.94x10⁻¹⁹ J.

I hope it helps you!