We’re being asked **to calculate the wavelength** being emitted by an orange light with an energy of **3.13 x 10 ^{-19} J**.

Recall that the ** energy of a photon (E)** is given by:

$\overline{){\mathbf{E}}{\mathbf{=}}{\mathbf{hv}}}\left(1\right)$

where:

**h** = Planck’s constant (6.626 × 10^{–34} J • s)

**v** = frequency (in s^{–1})

Also, recall that the frequency (v) and wavelength (λ) are related:

$\overline{){\mathbf{\lambda}}{\mathbf{=}}\frac{\mathbf{c}}{\mathbf{v}}}\left(2\right)$

where:

**c** = speed of light (3.0 × 10^{8} m/s)

A photon of orange light has energy of 3.13 x 10^{-19} J. What is its wavelength?

A. 700 nm

B. 635 nm

C. 590 nm

D. 562 nm

E. 494 nm