Is It Accurate to Measure the Elementary Charge with Just One Oil Drop?

In summary, the conversation was about completing the Millikan oil drop lab with as much accuracy as possible, using the PASCO interface and an accurate air pressure calibration. The final experimental charge of the electron was 1.8 x 10^-19 C, which resulted in a 12.5% discrepancy compared to the theoretical charge of the electron. The speaker questioned if it was wrong to contest the points deducted for having a single electron on the oil drop analyzed. They also mentioned having multiple measurements on drops and obtaining a final answer from averaging them. Another person in the conversation pointed out that it is not possible to measure the elementary charge with a single drop and asked how many electrons were present in the other drops.
  • #1
tvelev92
3
0
I completed the Millikan oil drop lab in class with as much accuracy as possible. I used the PASCO interface and used a very accurate Air pressure calibration. My final experimental charge of the electron derived from the equation in the lab was, 1.8 x 10 ^-19 C. When I turned in my lab, I was docked points for having a "very rare" one electron on the oil drop analyzed even though the percent discrepancy is something like 12.5 percent compared to the theoretical charge of the electron. Would I be wrong to contest this?

edit- usually the charge contained on one drop is due to several electrons and dividing by the theoretical charge gives you how many electrons are on it. I got one electron on the drop and got docked
 
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  • #2
how much cahrge did you get on a drop...if it was only 1.8 x 10-19C then it looks strange because that is close to exactly 1 electron
 
  • #3
That is the exact computed number from the equation
 
  • #4
wow..that is strange, sounds like you had a drop with exactly one electron on it.
Not impossible but also not likely.
Did you have lots of measurements on drops to get a final answer?
 
  • #5
Took 6 times up and 6 times down averages them separately and computed from there
 
  • #6
If I remember correctly, in this experiment I had 2 drops with a single electron, too. 2 out of ~30, with most somewhere in the range of 2-10 electrons.

You cannot measure the elementary charge with a single drop only. How many electrons did you have in the other drops?
 

1. What is the Millikan Oil Drop Experiment?

The Millikan Oil Drop Experiment is a famous physics experiment conducted by Robert A. Millikan in 1909 to determine the charge of an electron. It involved suspending tiny oil droplets between two charged plates and measuring their motion in an electric field.

2. What was the significance of the Millikan Oil Drop Experiment?

The Millikan Oil Drop Experiment provided the first accurate measurement of the charge of an electron, which was essential in understanding the structure of atoms and the behavior of electricity. It also helped to confirm the quantization of electric charge and led to the development of the atomic model.

3. What were the challenges faced during the Millikan Oil Drop Experiment?

One of the main challenges faced during the experiment was the difficulty in obtaining stable oil droplets and accurately measuring their motion. The equipment used for the experiment also had to be carefully controlled to eliminate any external influences on the droplets.

4. How did the Millikan Oil Drop Experiment impact the scientific community?

The results of the Millikan Oil Drop Experiment had a significant impact on the scientific community by providing a precise value for the charge of an electron and confirming the existence of quantized electric charge. It also helped to establish the validity of the atomic model and opened up new avenues for research in the field of atomic and subatomic particles.

5. Are there any controversies surrounding the Millikan Oil Drop Experiment?

There have been some controversies surrounding the Millikan Oil Drop Experiment, mainly regarding the accuracy of Millikan's results and the methods used to obtain them. Some scientists have also criticized Millikan for not acknowledging the contributions of his assistant, Harvey Fletcher, in the experiment.

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