Planck's Constant Apparatus

Advanced physics items are drop shipped. These products are built to order. Carolina does not hold stock. Please allow 90 days to receive your item from the time you place your order. This is the industry standard for this type of equipment.
Using Planck's Constant Apparatus, the classic experiment to demonstrate outer photoelectric effect and measure Planck's constant can be performed.
Learn the concept of quantization of light. Highly accurate under normal lab conditions, this apparatus includes 5 precision plug-in LED modules, a vacuum photocell, an integrated voltmeter and nanoammeter, and control circuitry, all in a compact, lightweight unit. Photocurrent range is 10-9 to 10-12 A. The picoampere amplifier unit provides a highly stable, well-shielded current amplifier and a very precise, stable source of the variable reverse voltage. The stabilized LED supply and amplifier routinely allow Planck's constant to be determined within 3%. Powered by a 50-W high-voltage mercury lamp, this lamp and a set of matching narrow-band interference filters rigorously exclude all light except the wavelength being measured.
The included instruction manual contains theoretical background, sample activities, and sample data. Recommended for advanced or college-level physics students. V-I graphs of the phototube output can also be plotted with an x-y recorder (not included) connected through the outlets on the back panel.
Specifications:
Picoampere Amplifier and Control Unit
Imposes a highly stable DC voltage of -2.000 to +2.000 V onto the photocell. The voltage is adjusted by a 10-turn potentiometer. The unit has a digital voltmeter and analog ammeter.
Voltmeter: 3-1/2 digit LED display
Current Measurement Range: 10-9 to 10-12 A in 5 steps
Zero Drift: < ±2% at 10-3 A over 8 hr (60 min after instrument is turned on)
Phototube Voltage Supply: -2.000 to +2.000 V, precisely adjustable, with error < 0.1%
Mercury Light Source (ballast is mounted in the base)
Housing has a window on the side, with a fixed diaphragm.
Lamp: GGQ-50-W high-voltage mercury vapor lamp
Spectral Range: 320.3 to 872.0 nm
Usable Spectral Lines: 365.0, 404.7, 435.8, 491.6, 546.1, and 577.0 nm
Interference Filters, Type ZG II, Medium Film
Type: Narrow-band, multi-layer film
Bandwidth: <50 nm
Wavelengths Supplied: 365.0, 404.7, 435.8, 546.1, and 577.0 nm
Diameter: 30 mm
Phototube, Vacuum, Type GD-2 (mounted inside photocell unit)
Anode: Nickel ring, 25 mm diam
Cathode: Ag-O-K
Window: Boron-silicon glass
Spectral Response Range: 30 to 700 nm
Peak Wavelength: 350 nm, ±20 nm
Minimum Cathode Sensitivity: 1 mA/lm
Dark Current: ~10-12 A
Ratio of Reverse Current to Positive Saturation Current: <0.5%
Condenser lens (installed in the light entry tube located on the front of the photocell unit)
Accuracy: < 5% with respect to the accepted value (h=6.62619 x 10-34 Js)
Power Supply: 110-V AC, 60 Hz
Dimensions: 280 x 120 x 160 mm
Weight: 1 kg (2-2/10 lb)
Policies
SHIPPING
Shipping is Extra and will be charged separately. Shipping Quotes will be given upon request.
REPORTING DAMAGED ITEMS AND SHORTAGES
All shortages, defects and deficiencies must be reported within 7 days of receiving the shipment. Merlan Scientific cannot assume responsibility for shortages reported after this period.
On receiving goods, check your packing slip and the package contents carefully. Please report any damaged items immediately and keep all shipping materials for inspection. If you have any questions please call 1-800-387-2474 or write us at info@merlan.ca.
RETURNING GOODS
Before returning any item to Merlan Scientific, please call for a Return Authorization Number. Shipments received without authorization may be refused.
WARRANTY POLICY
Merlan Scientific warrants that each product will be free of defects in materials and workmanship for a period set forth in its published user manuals for its system products and for a period of one (1) year for its component products. The warranty commences on the date the product is shipped by Merlan Scientific. Merlan Scientifics’ sole liability and responsibility under this warranty is to repair or replace any defective product, which is returned to it by the buyer, and which Merlan Scientific determines qualifies for repair or replacement under the terms of the applicable warranty. The product returned to Merlan Scientific for warranty service will be shipped to Merlan Scientific at the buyers expense and will be returned to buyer at Merlan Scientifics’ expense. In no event shall Merlan Scientific be responsible under its warranty for any defect, which is caused by negligence, misuse or mistreatment of a product, or for any unit, which has been altered or modified in any way. The warranty of repaired and replacement products shall terminate with the original warranty of the product.
tab-whats-include