Planks Constant Using LED’S OF Different Colours

This kit is used to determine Planck's constant using LEDs of different colors. Consist of stabilized power supply controlled by Multi – ten potentiometers. Two digital meters are provided on the panel for voltage & current measurement. Five different colours LED's are provided & LED selection via 4mm socket & suitable leads are provided with this instrument. Each LED has a specific threshold voltage at which electrons begin emission.