A new spin on the classic method of calculating Planck's constant, this apparatus provides a simple and effective means of studying the photoelectric effect, gaining a good value for h, and exploring basic quantum mechanics. Comprising a phototube and control unit with built-in voltmeter and nanoammeter, the apparatus can be used with three LEDs of known wavelength (included) to learn about the relationship between the energy of emitted electrons and the wavelength of incident radiation. Planck's constant can then be calculated approximately using the Planck-Einstein relation.The in-depth notes include explanations of a range of phenomena and theory associated with the photoelectric effect and Planck's work alongside the experimental methods.Includes:A phototube3 LEDs (green, red, and blue)Control unitPower supplyComprehensive teacher guide.Technical specifications:Power supply: 24V d.c.Voltmeter: 4 digits, sensitivity 2mVAmmeter: 4 digits, sensitivity 5nAButton to cut off currentLED light adjustment: 0-100%Anodic tension adjustmentDimensions:Control station: 190mm x 130mm, 50 x 60mmPhototube base 130mm x 180mm x 150mm, 50mmWeight:Control station: 370gPhototube base: 560g