# What is the relationship between photon energy and wavelength?

## What is the relationship between photon energy and wavelength?

Photon Energy and Wavelength. The energy of light (or photon energy), E, is inversely proportional to the wavelength by the equation: E = hc/ l (equation 1) where h is Planck’s constant (6.6261 x 10 -34 J*s) and c is the speed of light (2.9979 x 10 8 m/s).

What is the formula for the energy of a photon?

E = h * c / λ = h * f, where. E is the energy of a photon. h is the Planck constant, c is the speed of light, λ is the wavelength of a photon,

### How does Planck’s equation relate the frequency of a photon?

The Planck’s equation relates the frequency of a photon to its energy through a Planck constant h equal to The Planck constant is in the units (energy)* (time) and you can think of it as a conversion factor from energies to frequencies. f is the frequency of a photon.

What is the power of a short wavelength light source?

The power of short wavelength light sources in the EUV to X-ray range are often expressed as photon flux ( F) in the units of photons per second (ph/s). Average power is related to flux and photon energy by: For any given flux and wavelength (in nm), equation 5 can be used to calculate the corresponding average power (in m W).

#### How do you find the energy of the emitted photon?

In the hydrogen atom, with Z = 1, the energy of the emitted photon can be found using: E = (13.6 eV) [1/n f2 – 1/n i2 ] Atoms can also absorb photons. If a photon with an energy equal to the energy difference between two levels is incident on an atom, the photon can be absorbed, raising the electron up to the higher level.

How do atoms conserve energy by emitting photons?

To conserve energy, a photon with an energy equal to the energy difference between the states will be emitted by the atom. Consider the photon emitted when an electron drops from the n=4 to the n=2 state to the photon emitted when an electron drops from n=3 to n=2.