Question

Light with a wavelength of 614.5nm looks orange. What is the energy (in joules)?

a. 3.23 × 10⁻19
b. 2.56 × 10⁻19
c. 4.01 × 10⁻19
d. 1.23 × 10⁻19

Answer 1

The energy of a photon with a wavelength of 614.5 nm is approximately 3.23 x 10⁻¹¹ J, and which is equivalent to about 2.018 eV when calculated using Planck's formula and converted from Joules. so, option a is the correct answer.

Step-by-step explanation:

The energy of a photon with a wavelength of 614.5 nm can be calculated using the formula E = hc/λ, where E is the energy of the photon in joules, h is Planck's constant (6.626 x 10⁻³㎡ J⋅s), c is the speed of light in a vacuum (approximately 3 x 10¸ m/s), and λ is the wavelength of the photon in meters. Converting the wavelength to meters, 614.5 nm is 614.5 x 10⁻¹ m. Plugging these values into the formula, we get E = (6.626 x 10⁻³㎡ J⋅s) (3 x 10¸ m/s) / (614.5 x 10⁻¹ m) which equals roughly 3.23 x 10⁻¹¹ J.

To convert the energy to electron volts (eV), you can then divide the energy in Joules by the charge of one electron (1.602 x 10⁻¹¹ C), which results in the energy of the photon being about 2.018 eV.