Planck's Constant Experiment (by Photoelectric Effect)

The Planck's Constant Experiment by Photoelectric Effect is designed to determine Planck's constant and the work function of materials through the study of the photoelectric effect. The experiment demonstrates the phenomenon in which electrons are emitted from a metal surface when it is exposed to electromagnetic radiation of suitable frequency.

This apparatus provides a clear understanding of the fundamental principles of quantum physics and enables students to verify Einstein's photoelectric equation while determining important physical constants.

Features and Specifications

Photo-sensitive device

• High-quality vacuum phototube for detecting the photoelectrons generated during the experiment.

Light source

• Halogen tungsten lamp

• Rating: 12 V / 35 W

• Provides a stable, uniform source of illumination.

Colour filters

A set of precision optical filters is provided to obtain monochromatic light of different wavelengths:

• 635 nm

• 570 nm

• 540 nm

• 500 nm

• 460 nm

Accelerating voltage unit

• Regulated DC power supply

• Output voltage: ±15 V, continuously variable via a multi-turn potentiometer

• Display: 3½-digit LED with 7-segment indication

• Accuracy: ±0.2%

Current measuring unit

A highly sensitive digital nanoammeter is incorporated for measuring extremely low photoelectric currents.

Measurement ranges:

• 1000 nA

• 100 nA

• 10 nA

• 1 nA

Features:

• 100% over-ranging facility

• Resolution: 1 nA in the 1 nA range

• Display: 3½-digit LED

• Accuracy: ±0.2%

• Excellent stability and low-current measurement capability

Optical bench

• Precision optical bench with a 400 mm scale length

• Allows smooth movement of the light source to adjust the distance between lamp and phototube

• Includes a drawtube for easy insertion of colour filters

• Fitted with a focusing lens at the rear for proper light alignment and focusing

Power requirement

• 220 V AC ±10%

• Frequency: 50 Hz

Experiments

• Determine Planck's constant using the photoelectric effect.

• Determine the work function of the photocathode material.

• Study the relationship between stopping potential and the frequency of incident light.

• Verify Einstein's photoelectric equation.

• Investigate the characteristics of photoelectric emission.

Educational Applications

The apparatus is widely used in the physics laboratories of universities, engineering colleges and science institutions for experiments in modern physics, quantum mechanics and photoelectric phenomena.

We are manufacturers and suppliers of the Planck's Constant Experiment (by Photoelectric Effect), serving educational institutions and laboratories worldwide, including Algeria, Argentina, Australia, Bahrain, Bangladesh, Belgium, Bhutan, Brazil, Cambodia, Cuba, Cyprus, Denmark, Ecuador, Egypt, Ethiopia, Finland, France, Georgia, Germany, Ghana, Hungary, Iceland, Italy, Japan, Jordan, Kenya, Kuwait, Malaysia, the Philippines, Tanzania and Uganda.