Diffraction Experiment - Comparing theory with my data

In summary, the speaker is analyzing data from a diffraction experiment using a two slit diffraction grating with a laser source. However, the minima on their graph are shifted towards the origin compared to the theoretical plot. They are unsure of the reason for this and have considered the possibility of obtaining bad results. They are also less concerned about the minima not being at zero, attributing it to imperfect intensity. They are advised to check their values for slit separation and wavelength as these could affect the width of the pattern.
  • #1
poonintoon
17
0
Not sure if this is the right forum for this but I am analysing the data for the diffraction experiment I have just done (laser source at two slit diffraction grating) and have got the graph (similar to this http://www.physics.umd.edu/courses/Phys273/williams06/TwoSlit.jpg" [Broken]).
However all the minima for my data have been shifted towards the origin when compared to the theoretical plot. I have been racking my brains but can't think of any convincing reasons why this could happen other than the fact that I got bad results.
The minima are also not at zero but I am less concerned about this since I am assuming this is just down to not getting perfect intensity.

Thanks.
 
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  • #2
poonintoon said:
However all the minima for my data have been shifted towards the origin when compared to the theoretical plot.
Have you double-checked your values for slit separation and wavelength? (These would obviously affect the width of the pattern.)
 
  • #3


Thank you for sharing your data and concerns about your diffraction experiment. As a scientist, it is important to always compare our experimental results with theoretical predictions in order to gain a better understanding of the phenomenon we are studying. In your case, it is interesting to see that your data does not match the theoretical plot exactly, with the minima being shifted towards the origin.

There could be several reasons for this discrepancy in your results. One possible explanation is that there may have been some error in your experimental setup or measurement techniques. It is important to carefully check all the variables and parameters involved in the experiment to ensure accuracy. Additionally, it is possible that there may have been some external factors such as environmental conditions or equipment limitations that could have affected the results.

Another possibility is that the diffraction grating used in your experiment may not have been perfectly aligned, which could have caused the shift in the minima. It is important to make sure that the grating is properly aligned and that the laser source is centered on the slits.

It is also worth considering the possibility that the diffraction grating itself may have some imperfections or defects, which could have affected the results. In this case, it may be helpful to repeat the experiment with a different grating or to carefully examine the grating for any potential issues.

Lastly, as you mentioned, the intensity of the light may also play a role in the positioning of the minima. It is important to make sure that the intensity of the laser source is consistent throughout the experiment and that the measurements are taken at the same distance from the source each time.

In conclusion, while it is concerning that your data does not match the theoretical plot exactly, there could be several factors at play here. I would suggest carefully examining your experimental setup and techniques, as well as the diffraction grating itself, to determine the possible sources of error. It may also be helpful to repeat the experiment and compare the results. Keep in mind that in science, not all experiments will yield perfect results, and it is important to carefully analyze and interpret the data in order to gain a better understanding of the phenomenon being studied.
 

1. What is diffraction and why is it important in scientific research?

Diffraction is the bending or spreading of waves as they pass through an opening or around an obstacle. It is important in scientific research because it allows us to study the properties of light and other waves, and can also provide information about the structure of materials.

2. How does a diffraction experiment work?

In a diffraction experiment, a beam of light or other waves is directed at a sample with a regular pattern, such as a diffraction grating. The waves are then diffracted and produce a pattern of bright and dark spots, which can be observed and measured to determine the properties of the waves and the sample.

3. What is the theory behind diffraction and how does it relate to my data?

The theory behind diffraction is based on the principles of wave interference, which explain how waves interact with each other. By comparing the expected diffraction pattern based on this theory with your own data, you can determine if your results align with the predicted outcomes and if there are any discrepancies that may require further investigation.

4. How do I analyze and interpret the results of a diffraction experiment?

To analyze and interpret the results of a diffraction experiment, you will need to compare your data to the expected diffraction pattern and determine any similarities or differences. You may also need to take into account any sources of error or experimental limitations that could affect your results.

5. What are some common applications of diffraction experiments in different fields of science?

Diffraction experiments have a wide range of applications in fields such as physics, chemistry, biology, and materials science. Some examples include studying the properties of light, analyzing crystal structures, determining the structure of proteins, and examining the properties of different materials for various applications.

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