Physics Lab Equipment

LEAI-42 Apparatus of Millikan's Experiment - Advanced Model

LEAI-42 Apparatus of Millikan's Experiment - Advanced Model

Features

  • CCD acquisition and LCD display to eliminate eye fatigue

  • Electronic graduation scales on screen

  • Voltage, time and oil image displayed on one screen

  • Optional Brownian motion experiment with 120X objective






Introduction


The LEAI-42 Apparatus of Millikan's Oil Drop Experiment is an advanced version of the Millikan Oil Drop Experiment, designed to offer more precise measurements and a modern approach to studying the quantum nature of electrical charges. Unlike traditional setups, which rely on eyepieces and stopwatches, the LEAI-42 provides a sophisticated CCD image acquisition system that displays the voltage, time, and oil drop images on a screen simultaneously. This setup minimizes eye fatigue and ensures greater accuracy during the experiment, making it ideal for advanced educational purposes.


The LEAI-42 is engineered to verify the quantum nature of electrical charges, measure the elementary charge of an electron, observe Brownian motion, and explore the normal distribution of displacement probability in the movement of oil droplets. Its modern design offers a clearer, more accurate view of the oil drops and the forces acting on them, improving both the experience and the educational value of the experiment.


The instruction manual contains comprehensive materials including experimental configurations, principles and step-by-step instructions. Please click Experiment Theory and Contents to find more information about this apparatus.

 

This apparatus possesses the following advantages:

 

1. Electronic graduation scales are stable, not affected by the distortion of the display.

2. Image of oil drops is clear and bright with a high contrast.

3. Better observation of Brown movement with a 120X TV microscope.

4. Graduation scale, voltage, time, and oil drop image displayed on one screen.

5. Output signal compatible with various display devices such as TV, projector, recorder and so on.

 

Using this apparatus, the following experiments can be conducted:

 

1. Verify the existence of positive and negative electrical charges

2. Verify the quantum nature of electrical charges

3. Measure the elementary charge of an electron

4. Observe and measure Brownian motion (optional)

5. Verify normal distribution of displacement probability (optional)


Specifications

DescriptionSpecifications
Operating voltage between upper and lower platesDC ± 0 ~ 700 V, adjustable, 3-1/2 digit, resolution 1 V
Elevation voltage200 ~ 300 V
Distance between upper and lower plates5 ± 0.01 mm
Magnification of objective lens60X and 120X
Electric timer0 ~ 99.99 s, resolution 0.01 s


Electronic graduation of scale

Type A: 8×3 grid, 0.25 mm/div with 60X objective
Type B: 15×15 grid, 0.08 mm/div with 60X objective

& 0.04 mm/div with 120X objective


Parts List

DescriptionQty
Main unit1
Oil sprayer1
Bottle of oil (15 mL)1
LCD monitor (9-inch)1
120X objective lens1
Power cord1


      Apparatus of Millikan's Experiment.png

Schematic diagram of oil drop chamber


1 oil mist cup, 2 oil shutter, 3 windscreen, 4 upper electrode, 5 oil drop channel, 

6 lower electrode, 7 base stand, 

8 cover, 9 oil spray aperture, 

10 oil mist aperture, 11 electrode clamp, 12 oil channel base


      Apparatus of Millikan's Experiment.png

Schematic of upper panel of main unit

(Click figure to enlarge)

      Apparatus of Millikan's Experiment.png

Quantity of elementary charge vs total charges carried by various oil drops

(Click figure to enlarge)

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