Apparatus for Determining Planck’s Constant Advanced Physics Experiment

This Planck's Constant experiment system is designed to investigate the photoelectric effect by measuring the current-voltage (I-V) characteristics of a photoelectric tube under monochromatic light of different wavelengths. It enables students to determine Planck's constant, calculate the work function and cut-off frequency of the photocathode material, and verify Einstein's photoelectric equation. The system incorporates a grating monochromator for accurate wavelength selection and precise photoelectric measurements. Physics Lab Experiments from Atico Exports.

Experiments :

• Measure the Current-Voltage (I-V) Characteristic Curve of a Photoelectric Tube.
• Plot the Stopping Voltage Versus Frequency (U–ν) Curve.
• Calculate Planck's Constant (h).
• Calculate the Cut-Off Frequency (ν) of the Photocathode Material.
• Calculate the Work Function (Ws).
• Verify Einstein's Photoelectric Equation.

Light Source :

• Tungsten-halogen lamp
• Rating: 12 V / 75 W
• Spectral range: 350–2500 nm

Grating Monochromator :

• Wavelength range: 200–800 nm
• Focal length: 100 mm
• Relative aperture: D/f = 1/5
• Grating: 1200 lines/mm (blazed at 500 nm)
• Wavelength accuracy: ±3 nm
• Wavelength repeatability: ±1 nm

Photoelectric Tube :

• Working voltage: -2 V to +40 V
• Continuously adjustable
• 3½-digit digital display
• Spectral response range: 190–700 nm
• Peak wavelength: 400 ± 20 nm