APU SCIN 133 Physics Lab 5
Physics Lab 5The photoelectric effectThis lab will examine the photoelectric impact. The photoelectric impact is the emissionof electrons from a floor when illuminated with mild of a sure frequency. The firstinsight to understanding this phenomenon was introduced in 1900 by Max Planck. Hisformula, E = hf, associated the vitality of a photon to its frequency. Albert Einstein extendedthis concept of quantized photonic vitality to a stream of photons (electromagnetic radiation)and defined the photoelectric impact.This digital experiment is a Java Applet. Applets require the JVM (Java Digital Machine).It's not unusual for the JVM to be outdated or not put in on a pc system,inflicting the applet to fail to run correctly if it runs in any respect. In that case you need to obtain(free of charge) and set up the most recent model fromhttp://java.com/en/obtain/handbook.jspSome community directors block Applets. In that case, contact your networkadministrator or attempt a distinct Web entry level.Directions:1. Go to http://phet.colorado.edu/sims/photoelectric/photoelectric_en.jnlp2. Enhance the depth to 50%. It is best to discover the ejection of elections from thesurface.three. Slowly improve the wavelength () of the sunshine till electrons are not ejectedand report the wavelength () within the desk under.four. Calculate the frequency (f) for that wavelength and report it within the desk under.Do not forget that c=f, the place c is the pace of sunshine (three * 10^eight m/s).5. Calculate the Vitality (E) in joules for that wavelength and report it within the tablebelow. Do not forget that E = hf, the place h the Planck fixed (6.6 *10^-34 j*s)6. Full the Vitality (E) in electro-volt (ev) and report it within the desk under.1 electron-volt (eV) = 1.6 X 10-19 J7. Repeat the above step for every of the metals below the pull down menu.WavelengthFrequency fEnergy EEnergyMetal(nm)(Hz)(J)(eV)Sodium541nmZinc290nmCopper270nmPlatinum200nmCalcium430nm8. The minimal frequency of a photon that may eject an electron from a floor iscalled the edge frequency, ft. What's the threshold frequency, ft, for every of themetals?HINT: revisit directions three & four.MetalThreshold Frequency ft(Hz)SodiumZincCopperPlatinumCalcium9. The minimal quantity of vitality required for an electron to flee from a metallic iscalled the work perform (W) and is given by the equation W = hft. What's the workfunction for every of the metals in joules and electron-volts? HINT: revisit instructions3 to six.MetalWork Operate E(J)Work Operate E(eV)SodiumZincCopperPlatinumPlatinumCalcium10. Make the next further changes to the simulation.Test the field present vs. mild depth.Test the field electron vitality vs. frequencySelect the Sodium.Use violet mild (about 400 nm).Fluctuate the depth of the sunshine and observe any adjustments within the quantity ofejected electrons.Fluctuate the depth of the sunshine and observe any adjustments within the quantity ofejected electrons.11. Whats the connection between the depth of the incident mild and the quantity ofthe ejected electrons?12. Whats the connection between the depth of the incident mild and the vitality ofthe ejected electrons?