How does photon energy relate to frequency

Active 5 years, 11 months ago. Viewed 3k times. Improve this question. Community Bot 1. Add a comment. Active Oldest Votes. Improve this answer. DanielSank DanielSank The photoelectric effect you refer to: seems to say the opposite, that the energy of each photon is the same and what changes is the amount of photons per area.

Second, increase the energy per photon. This requires increasing the frequency. Timaeus Timaeus Sign up or log in Sign up using Google.

One such type of decay is a nuclear isomerization. In an isomerization, a nucleus rearranges itself to a more stable configuration and emits a gamma ray. While it is only theorized to occur, proton decay will also emit extremely high energy photons. Light incident on a metal plate may cause electrons to break loose from the plate surface Fig.

This interaction between light and electrons is called the photoelectric effect. The photoelectric effect provided the first conclusive evidence that beams of light was made of quantized particles. The energy required to eject an electron from the surface of the metal is usually on the same order of magnitude as the ionization energy. As metals generally have ionization energies of several electron-volts, the photoelectric effect is generally observed using visible light or light of even higher energy.

At the time this phenomenon was studied, light was thought to travel in waves. Contrary to what the wave model of light predicted, an increase in the intensity of light resulted in an increase in current, not an increase in the kinetic energy of the emitted electron. Einstein later explained this difference by showing that light was comprised of quantized packets of energy called photons.

His work on the photoelectric effect earned him the Nobel Prize. The photoelectric effect has many practical applications, as current may be generated from a light source. Generally, the photoelectric effect is used as a component in switches that respond to light. Some examples are nightlights and photomultipliers. Usually the current is so small that it must be amplified in order to be an effective switch.

The energy of a photon is a discrete quantity determined by its frequency. This result can be determined experimentally by studying the photoelectric effect. The kinetic energy of an emitted electron varies directly with the frequency of the incident light. If the experimental values of these energies are fitted to a line, the slope of that line is Planck's constant. The principle of conservation of energy dictates that the energy of a photon must all go somewhere.

The results from a photoelectric experiment are shown in Figure 2. The solid lines represent the actual observed kinetic energies of released electrons. The dotted red line shows how a linear result can be obtained by tracing back to the y axis. Electrons cannot actually have negative kinetic energies. Whereas the double slit experiment initially indicated that a beam of light was a wave, more advanced experiments confirm the electron as a particle with wavelike properties. The diffraction of a beam of light though a double slit is observed to diffract producing constructive and destructive interference.

Modern technology allows the emission and detection of single photons. In an experiment conducted by Philippe Grangier, a single photon is passed through a double slit. The photon then is detected on the other side of the slits. Across a large sample size, a trend in the final position of the photons can be determined. Under the wave model of light, an interference pattern will be observed as the photon splits over and over to produce a pattern.

However, the results disagree with the wave model of light. Each photon emitted corresponds with a single detection on the other side of the slits Fig.

Over a series of measurements, photons produce the same interference pattern expected of a beam of photons. When one slit is closed, no interference pattern is observed and each photon travels in a linear path through the open slit. According to the modern theory concerning atoms, electrons move in orbits around the nucleus.

If an electron absorbs energy it is promoted to a higher energy orbit. This situation is so unstable that after a very small period of time much less than a second and then it falls back to its previous orbit.

During the fall it emits a photon. The energy of a photon depends on radiation frequency; there are photons of all energies from high-energy gamma- and X-rays, through visible light, to low-energy infrared and radio waves. This means more energetic high frequency photons like X-rays and gamma rays travel at exactly the same speed as lower energy low frequency photons, like those in the infrared. Because wavelength and frequency are determined by each other, the equation for the energy contained in a photon can be written in two different ways:.

One of the strangest discoveries of quantum mechanics is that light and other small particles, like photons, are either waves or particles depending on the experiment that measures them. When light passes through a prism they spread out according to wavelength.

Contrarily, bombard metal with light, and it displays a particle side of its nature, where only photons that have more than a specific amount of energy release electrons. This experiment, called the photoelectric effect , is what won Einstein his Nobel Prize. Photons with insufficient energy can hit metal, yet won't knock any electrons loose.