Apparatus for Determining Planck’s Constant Physics Lab Experiment

This photoelectric effect experiment system is designed to investigate the fundamental principles of the photoelectric effect and accurately determine Planck's constant. It enables students to measure the cut-off voltage, analyze the relationship between photocurrent and incident light, and verify the laws of the photoelectric effect. The system features a high-sensitivity microcurrent measurement unit, precision optical components, and optional computer-based data acquisition through a USB interface. Manufactured by Atico Export India.

Experiments :

• Measure the Cut-Off Voltage and Calculate Planck's Constant.
• Measure the Photocurrent of the Phototube and Study the Photoelectric Effect.

Microcurrent Measurement Range :

• 10⁻⁶ A to 10⁻¹³ A
• 6 measurement ranges
• 3½-digit digital display
• Zero drift: ≤2 digits/min

Diaphragm and Filter Assembly :

• Diaphragm and color filter rotate independently without interference
• Smooth operation
• Prevents direct light from entering the phototube

Photocell Operating Voltage :

• -2 V to +2 V
• -2 V to +30 V
• Fine adjustment
• Stability: ≤0.1%

Phototube Spectral Response :

• 340–700 nm

Cathode Sensitivity :

• ≥1 μA

Dark Current :

• <2 × 10⁻¹² A

Anode :

• Nickel ring

Color Filters :

• 365.0 nm
• 404.7 nm
• 435.8 nm
• 546.1 nm
• 578.0 nm

Light Source :

• 50 W high-pressure mercury lamp
• Dedicated power supply

Planck's Constant Measurement Error :

• ≤3% compared with the theoretical value

Computer Interface :

• USB interface
• Supports optional computer-based experiments and data acquisition