Plancks Constant Kit
Product Code : JA-PLE-7945
The Plancks Constant Kit (SKU JA-PLE-7945) is a self-contained set-up, supplied by JaincoLab, for determining Planck's constant h in college and senior-school physics practicals. It uses the LED method: the voltage drop across light-emitting diodes of different colours is measured at a constant current and related to the wavelength of the light each one emits. This Planck's constant kit using LEDs includes its own power supply, digital meters and four calibrated LEDs, so no other accessory is needed.
Specifications
The kit combines a variable power supply of 0 to 5 V adjustable in 1 mV steps, a digital microammeter, a built-in 0 to 9 V digital voltmeter that reads the voltage across the LED under test, and four calibrated LEDs of different colours, and it needs no other accessory.
| Product | Plancks Constant Kit |
| SKU | JA-PLE-7945 |
| Method | Voltage drop across LEDs of different colours at constant current |
| Power supply | Variable, 0 to 5 V, adjustable in steps of 1 mV |
| Current meter | Digital microammeter |
| Voltmeter | Digital, 0 to 9 V, built in |
| LEDs | 4 calibrated LEDs |
| Accessories needed | None; the kit is self-contained |
Experiments with the Planck's constant kit
Students set a constant current through each LED in turn, read the voltage across it and plot that voltage against the reciprocal of the emitted wavelength; because the photon energy eV equals hc divided by the wavelength, the gradient of the line equals hc/e, from which h is calculated.
- Determining Planck's constant h from LEDs of four colours
- Showing how LED forward voltage relates to the colour, and so the wavelength, of the emitted light
- Introducing band gaps: light is emitted when electrons cross the energy gap at the p-n junction
- Modern physics practicals in B.Sc, engineering physics and senior-secondary classes
Scope of supply and ordering
The listing covers the complete kit: the variable 0 to 5 V power supply, the digital microammeter, the 0 to 9 V digital voltmeter and four calibrated LEDs. Accessories, spares and quantities are confirmed on the quotation.
Minimum order quantity, lead time and packing are confirmed on each quotation for the number of kits and the delivery destination. JaincoLab supplies single kits for a college laboratory, several kits for student groups, and bulk institutional and tender orders, including export to Africa, the Middle East and South and South-East Asia.
Frequently asked questions
How does the kit determine Planck's constant?
The voltage across LEDs of different colours is measured at a constant current. A graph of this voltage against the reciprocal of the wavelength is a straight line whose gradient gives h.
What is included in the kit?
A variable power supply of 0 to 5 V adjustable in 1 mV steps, a digital microammeter, a 0 to 9 V digital voltmeter and four calibrated LEDs.
Does it need any other equipment?
No. The kit is self-contained and requires no other accessory.
Related products
- Planck's Constant By LED
- Forbidden Energy Gap Kit
- LED and Laser diode Characteristics Apparatus
- Planck Constant Apparatus
Other modern physics kits are listed under Physics Lab Equipments; the full JaincoLab catalogue is under physics lab equipment.
Request a quote
To ask for a price on the Plancks Constant Kit, send the number of kits and the destination through the JaincoLab contact page or email [email protected].
Companies bidding for Ministry of Education, World Bank or United Nations laboratory tenders can work with JaincoLab as their manufacturing partner: we make and export complete laboratory packages for such projects and have executed them successfully in many countries. Send the tender specification through our tenders page for a quotation.
