#### Related to [[Electrons]], [[Photon]]s and [[Electromagnetic radiation]]. --- ## Definition - For every metal, when electromagnetic radiation *(such as light)* hits it as long as it the metal can release an [[Electrons]] *known as photoelectrons*. --- ## More info - It was discovered by **Hertz** in 1887 by irradiating metal plates with high energy beams of light. He observed [[Electrons]] being released thus, creating a current. - As the frequency increases *past* the minimum frequency the KE of emitted electrons also increases **proportionally** but the number of emitted photons stays the same. - There is a *minimum* frequency / energy of the [[Photon]] required for the metal to eject an electron past which the greater the frequency the greater the electron's energy. - The greater the **Intensity** of the light the more electrons are released. --- ## Equations - **NOTE:** A *work function* is the amount of work in Jules required for the electron to come off of the metal or atoms that it is bound to. >[!Photoelectric Equations] >- **Remember that E0 is also the work W**. ><br> > >![[Pasted image 20230111130340.png | 621]] > >- **In the following equation E0 is the minimum energy required to eject an electron from the metal's surface and KE is the energy of the released [[Electrons]]. ** > >![[Pasted image 20230111130457.png]] > >![[Photoelectric effect.png]] --- ## Strange wording ==Important!== - Sometimes the question will ask for the *wavelength* of light required to **ionize** a specific element. This is in other words the wavelength of light required for the **photoelectric effect** to happen, causing that element to release an [[Electrons |Electron]] forming an [[Ion]]. --- #mainpage